Green Energy

How to Make PVC Wind Generator Blades?

2012-02-25T10:23:00.003-08:00

The PVC generator blades are becoming more and more popular with domestic and homemade wind generators. It is quite easy to find raw PVC materials as they are relatively cheap. Even then, making the right blades from the PVC materials is the most challenging part of creating own wind generator. This is because the blades have to get exposed to very high stress when producing energy. To ensure that the blades withstand destructive vibrations, they must be made with high tolerances.

Why you need PVC for your wind generator blades?

First, PVC pipes are easily available and they are cost effective thus can be replaced easily upon damage. Secondly, the PVC materials are highly flexible thus reducing the risk of frequent damage as well as prevent wind turbines from over spinning. Lastly, they PVC pipes are easy to work with as lesser energy is required to cut them into the blade shapes that you may require. To make the best out of the PVC materials used to make blades, ensure that they are of the right thickness to ensure that the blades once created do not bend too much to hit the turbine mast.

How to make PVC wind generator blades?

1.) First, assembly all the tools you may need during the actual procedure. Then, measure the PVC pipe's circumference; you can use either a paper or a string to do that. Then, measure the pipe's length using a tape measure. Then, using the length measurements, divide the pipe into equal parts. You can decide to come up with four pieces. If your pipe measured say 16 inches and you need 4 pieces it means that each piece will be 4 inch long.

2.) Then using the tape measure again the pipe four times to show where the cuttings are to be made

3.) Next, wrap the pipe at one edge with a strip of paper that then make four marks around the paper to cover the circumference of the pipe. Armed with your hacksaw or jigsaw cut the pipe lengthwise using the marks you had previously made. Repeat this until you get the four pieces you had bargained for when you were marking the pipe. At the end of it all, you expect to come up with four pieces that have equal lengths, curvature and widths.

4.) Then from one corner of the four pieces, cut off about 2 inches and you will remain with a portion that is stable to mount the blade.

5.) Then starting from the corner that is on the opposite side of the cut corner, mark two inches. Next, create a straight line diagonally crossing the pipe from the place you marked to the other end of the pipe. Repeat this procedure for the other three pieces. On every pipe cut along the diagonal marks you made. With this, you will end up with triangular pieces that offer the windmill blade shape.

6.) Then, sand the blades to do away with the rough edges. Do this until all the four blades have smooth surfaces. With this, you will be ready to install into your wind generator. To create the surface, you will either need to bolt or screw the blades onto a hub preferably made of plywood. Alternatively, you can decide to use a car radiator fan and screw the blades onto the fan.

You may be required to coat the pieces with paint that is UV protective before installing the blades. Although the majority of PVC materials are strong enough to withstand a number of conditions, long exposure to UV rays will make them become brittle. The paint will ensure that the PVC material does not become brittle after some time of usage.

Decomposers and Detritivores in the Energy Pyramid

2012-02-25T10:17:00.000-08:00

In order for a natural ecosystem to be balanced there is need for three types of organisms; producers, consumers and decomposers. Producers are groups of organisms that make organic compounds out of inorganic ones. They include green plants that use energy from the sun to make their own food. Consumers get their nutrients from feeding on other organisms.

Decomposers help in converting the leftovers of animals and plants to useful substances for other living organisms. They are mainly bacteria and fungi. Have you ever wondered what would happen if the decomposers and consumers were not in the ecosystem?

Detritivores play a very important in the cycle as they are the consumers of dead leaves, old skin, carcasses and manure. They include millipedes, earthworms and slugs that feed on dead plants and animals but leave some parts and their feces that are converted to energy by the decomposers. Players in the energy cycle function hand in hand, a decomposer is found at the lowest part of the cycle as it deals with the remains. They complete the energy cycle. The roles of the decomposers and detritivores almost coincide.

Detritivores

Detritivores improve the nutritional value and the texture of the soil: This makes the soil productive to plant life which translates to availability of food for the herbivores and carnivores like human beings. They however do not complete the energy cycle as their wastes are energy products that need to be decayed. Consumers may eat an animal or plant but it will leave some amount of energy in form of fur and bones.

Get rid of dead organisms: They feed on dead organisms both plants and animals. They assist in ridding the environment of remains of organic material.

Decomposers

Decomposers actually help in the process of decay: They convert what is left by the detritivores that is the wastes and leftovers of bones and fur. This is converted to carbon dioxide used by plants for making its own food.
This is an indirect contribution to the provision of oxygen used for breathing. Plants take in carbon dioxide during photosynthesis and release oxygen which is essential for the lives of animals.

Adding nutrients to the soil: Decomposers break down non usable compounds in the air like magnesium and nitrogen into simple elements that can be used by plants or absorbed into the soil. These broken compounds enrich the soil increasing the chances of survival of plant life.

They keep the environment clean and healthy: Decomposers help in decay and conversion of remains of plants and animals to carbon dioxide and energy. This means that if decomposers were not there in the ecosystem we might have to cope with the stench that comes from overstayed dead parts of animals and plants like bones and leaves in the surrounding.

Generally, decomposers are the most recognized players in the food chain as well as the energy pyramid. They are the only other players that have direct access to the energy stored in plants that comes from direct sunlight. The other player is the herbivore which feeds on living plant life. The herbivores are known to consume only 10% of the energy in plants while the rest is consumed by decomposers who consume dead plants.

The decomposers do not share the energy with any members of the ecosystem but is transferred to the soil when they die or is taken away by the organisms that eat them. It is clear that survival would be difficult if the food chain lacked decomposers and detritivores. The energy cycle would not continue as the energy would be lost after the death of plants and animals.

Grid Tie Inverters for Solar Energy

2012-02-23T11:02:00.002-08:00

Having a solar system at home to convert sunlight into electrical power for domestic use is very beneficial to a person in several ways. Apart from having an uninterrupted power supply that is very much reliable, you get to save costs that would be used to foot electricity bills thus an appropriate source of power.

Connecting the solar to a power grid is one of the most common ways of configuring it at home because it ensures surplus power does not go into waste as well as producing extra power when the sunlight levels are low and at night when there is completely none. Owing to the benefits it comes with, this article will take you through the main steps of wiring grid tieinverters for solar energy at home to ensure you do not seek professional help when installing yours.

Getting Tools of Trade Ready

To begin with, you will be required to have all the necessary materials and equipment for wiring well in place and in advance. Make sure the solar panels, combiner box, direct current breaker box, grid disconnects and power inverter is ready and in good working condition. Once all that is ready, wire each string of the solar panels into the combiner box and make sure the circuit breakers are also in place. The number of solar panels you are using will determine the type of box and size of breakers that you require and this is vital for consideration to ensure you do not use wrong ones.

At the exact point where cables running from the panels enter the house install the direct current disconnect switch and then fix a metal oxide variator to the point where connections from several devices meet. This will be helpful in preventing circuits from any effects occasioned by excess currents or voltage thus minimizing chances of fire outbreaks in case of faults within the electrical system.

You can then install the breaker box which plays the role of a cutoff point because it acts swiftly to open the circuits whenever power leakages are detected. Do the same to the power inverter and this is important since it changes direct current that comes from the solar panels into alternate current which is the most common one in many homes. This furthermore makes sure the voltage of the current that comes from the panels is neutralized in a way that it is well suited for use with all the electrical apparatus like iron box, TV, radio and heaters you have.

Since there are times when you will not be willing to use the power or it is not necessary at all you will have to install the main service disconnect. This will enable you to cut the power supply between the system powered by the grid and the solar panels when not in use. Once you are through with all that, it is time to connect the main device disconnect to the power grid meter as well as the distribution panel. You will have tied together the solar system, utility lines and the power outlets in your house to enjoy uninterrupted power supply for free.

Caution while Wiring Your Grid Tie Inverters

Solar energy can be very dangerous like normal electricity especially when there are a lot of sunlight therefore you have to be extra careful when making the connections. Never leave any cables naked and seek advice from a qualified and experienced electrician before doing connections to avoid making wrong configurations. Also, take note that the entire system is connected together and the failure of one will lead to the failure of the rest which means you have to be cautious when using any.

How to Build a Vertical Axis Wind Turbine?

2012-02-22T09:47:00.000-08:00

There are various parts which are required to build a vertical axis wind turbine and below those are mentioned:

Parts Needed for Building the Vertical Axis Wind Turbine

Jigsaw and or band saw, a hand saw, a lathe, a drill press or hand drill, some drill bits, screwdriver, tab tool, a ruler, a pencil, compass, sanding paper, vise (it's meant to make work easier), wrenches, and 2 clamps. Then you may need some parts for this process which are a PVC pipe, waterproof wood "the concrete plywood is most advisable.

However, in the event you don't have one then you may be required to protect the plywood using a coating, 2 bearings and it is important to note that the one at the bottom will require to be firm to hold a load, a grease nipple, a wire rod in two sizes or 1 big one and some four small ones otherwise stainless steel is the best, have some bolts and washers in two sizes still the stainless steel is the best, get a piece of 40 mm round aluminum or its alloy such that it can handle a load, find two angle irons and three eye screws.

Steps on How to build the Vertical Axis Wind Turbine (VAWT)

First and foremost you will need to measure the PVC pipe which you will divide it into four equal parts using one of the saws. Then still cut it over through the whole length which should result into 8 equal size pieces.
The next step is take your two pieces of the waterproof plywood which should be 12mm then measure them in two directions whereby you mark the point from the middle of your plate. After which you take the compass and then draw a 40cm diameter circle. Then using your jigsaw to cut the plywood out.
The next step is to ensure that take the one of the half pipes then hold them against the 8 lines you had drawn previously. Ensure that you draw one line on the inside the circles and another one on the outside in a way you will make small bows of which you will have to clamp the bows together. Then cut them into equal pieces whereby you make a marking that runs over sides the two disks. This is meant to ensure that the turbine disks are lined up impeccably. In addition, ensure that the clamped disks are drilled to fit in the size of the big wire rod into the whole and then drill the four holes which are meant for the small rods. Then divide the four rods in similar sizes over the turbine ensuring that you stay 2cm from your bows. This will ensure that the washers do not come into contact with your blades.
The next step is that you place the turbine on top the same way you did at the bottom. Be keen on the markings that you had on the disks sides as they were still clamped. Then ensure that the cuts fit on top of each in a nice way as this will ensure that the turbine will not wobble as much after you are done. You can use a small piece of wood and hammer to reduce the risks of damaging the blade once you start hitting them. Also ensure that the blades fit in tightly and the little rods are in their right places.

In other terms, it may not be easy to build a VAWT but it will require understanding the instructions and if possible visit a website that will have all the right images to assist in making the bow cuts and finally having the wind turbine. It is important to note that most of the turbines require precise measurements that will assist in making the turbine having a more sturdy structure and get efficient.

Multifunctional Biomass System

2012-02-21T01:18:00.001-08:00

Biomass is known to play a big role in mitigating greenhouse gas emissions by supplyingbiomass based fuels. Low share of biomass application in many parts of the globe is eminent, and this is attributed to the high production costs and low availability of agricultural land where efficient biomass energy can be produced.

However low costs biomass production routes have been developed so that enough biomass energy is produced and put into useful purposes. One of the low costs production costs that has proven to be very effective and quite beneficial is the multifunctional biomass system. The system uses the concepts of multi- product use and cascading to produce the desired energy and for different applications within the home. Cascading refers to the use biomass in recycling of materials and energy recovery.

One of the vital parameters of multifunctional biomass systems is that, they offer chances for great savings of the nonrenewable energy consumption, greenhouse gas emission reduction, and saves on costs of agricultural land use and the total cost of multifunctional biomass system. The potential of the system to improve the costs is carried out in quantitative terms which are divided into two major aspects.

Aspects on how multifunctional biomass system saves on costs of land use, gas emissions and non-renewable energy consumption

One of the most important aspects that shows how multifunctional biomass system saves or improves on the costs of these applications, is the methodology to account for land use, greenhouse gas emission, nonrenewable energy consumption which are adapted for evaluation of the multifunctional system. It involves taking into account the time dimension and the integration of market prices which often change from time to time.

The environmental impact of biomass and system expansion are given special attention because, there is a positive impact on the environment which means that less money is involved in energy conversion systems. The other potential benefit largely depends on the kind of biomass system used. Good research needs to be carried out so that a profitable multifunctional biomass system is used, to help in fast and efficient energy production that is very useful.

Quantitative benefits of multifunctional biomass-refinery system

Multifunctional biomass-refinery system is largely used in the production of biomass energy. This includes the use of agricultural residues for energy production and the use of waste to energy for recovery. The level of systems performance in carrying out these tasks is quite exceptional and it doesn't take a lot of time and energy to produce the desired energy. This means that a fast energy production involves low costs of production in terms of the materials used per kilogram, which saves on production costs and land use. The market prices of and land may be high but since the system can operate faster, less materials and products and the products which are used are maximized so that they can produce the desired energy.

All bio-refinery multifunctional biomass systems can offer net savings of non-renewable energy consumption of 70 to 220 GJ per hectare every year, and net savings on greenhouse gas emissions of 3 to 17 mg every year per hectare. These are great net benefits that the system offers and that is why it is very important to ensure proper viability of biomass system, for increased production of energy and more opportunities for savings.

Multifunctional biomass should also be introduced on large scale so that good own price elasticity is achieved because, high demand of energy production materials affect the overall costs of biomass refinery system. With large scale introduction of biomass material, then there will production of an energy which can be used for various applications within and outside the house.

How to Build a Solar Power Windmill?

2012-02-20T11:52:00.000-08:00

With the harsh economic period that is being witnessed in the entire world, it is important that you derive ways in which to handle this situation. It is believed that human activities have greatly contributed to the economic crisis as well as to the harsh climate conditions that have caused unpredictable weather conditions. This is because these human activities affect the environment thus to reduce these effects, it is good to consider some of the activities that are harmful. One such way to protect the environment is to use solar power windmill. This is possible in that it will save lots of energy as well as costs. It is possible to build solar panel on your own.

How to Build a Solar Power Windmill?

The first thing that you need to do is to plan your system. Here are some ways to attain this;

You need to plan your system: This is the initial step when it comes to building a solar power windmill. In this step, you need to know how much energy you consume on daily basis or per month and also look at the monthly bills. You also need to cut wasting electricity in that you have to switch off lights when not in use also ensure some of the electronics in your house are put on power strips. You the need to add the entire wattage used on daily basis and also the amount that is used by your appliances. This is advised in that you will know the exact output of solar power windmill that you need in your home.

With this information, you need to research the market so as to find out the available solar power windmills as well the price. In this case, look at the features of these windmills such as battery durability which is important in that it will help establish the amount of energy that will be saved. Consider a battery that saves energy in at least two consecutive days.

You also need to evaluate solar output as well as the wind speed. This in most cases has to be done with the location in mind. Consider the wind turbines diameter so as to know the right turbine and solar to opt for. You can decide to purchase a kit or Build a Solar Power Windmillon your own. This is a decision that you need to regard.

Putting together the items

After you have determined what you need and shopped for the right products, it is time to build a Solar Power Windmill.
You need to install the solar panels on a designated place on your roof. This place should be where the sun hits so much. Consider the southwest facing side.
Erect windmill tower in a location where wind can easily reach the turbine blades without any form of hindrances from the environment. In order to boost performance, it is good to raise the tower.
Fix the turbine to the tower and during this process, ensure that the blades are of adequate length and that they have been pitched so as to catch prevailing wind and enhance free turning.
You then have to attach the windmill to a generator or alternator which is mandated to change wind power into electricity.

Finally, you have to wire the solar panels, generator as well as the battery to the electrical system. You need to be aware that the solar panels that you will install only generate electricity when light strikes onto them hence the amount of energy produced can vary from time to time. In case of temperature change, production of electricity will also be affected.

Passive Solar Biodiesel Storage

2012-02-18T19:45:00.000-08:00

Among the many projects in the homes that incorporate solar energy is the use of passive solar for biodiesel storage. Cold weather usually blocks the flow of fuel and fuel pumps. Biodiesel is the type of fuel obtained from bio gas of crops, livestock and food wastes and is used for cooking or heating and by some vehicles. The problem of storing biodiesel in cold season can be solved by using passive solar biodiesel storage.

This involves the use of passive easy to build solar sheds that heat themselves up with sun energy. Any vehicles using biodiesel or containers of biodiesel must be kept in heated conditions. This type of storage involves using renewable resources that help to contribute to environmental protection; that is the sunshine. Well monitored, these sheds of sunshine storage can keep fuel to 25 degrees above outside temperatures.

How to solve the chilling problems of bio fuels?

In using biodiesel, certain problems may arise like the chilly problems of bio fuels including gelling, the fuel lines and injectors clogging. The oil may also saturate or cloud. These are problems that can be solved by proper use of biodiesel storage facilities like the solar sheds described below. When biodiesel gels, it is not realistic to dissolve the accumulated crystals by reheating it. Heating the fuel may lead to.

The Solar sheds

Stored solar heat can be used to generate electricity that can help to keep biodiesel warm and flowing. To do this, a solar shed is required. These are houses made from wood, straw and clay. The interior of such a house have a lot of thermal mass for storage of captured solar energy. This is in form of adobe blocks, concrete floors and walls with fiber tubes that can take in the sun from outer space. The thermal mass material is dense to capture and store the heat from the sun. Proper venting systems are used to ensure spreading of the solar heat to cooler interiors and moveable insulation will enhance their workability in winter.

The solar shed construction can however be a tedious process that takes a lot of energy and time but the end results are worthwhile. This kind of structure will survive temperature changes as its temperature is constant. The solar structure may be constructed to meet the desired need therefore its size will depend on the storage needs. Some people may prefer insulating the interior of the shed with straw. However, this may be dangerous in case of fire. The solar shed method of storing biodiesel is very practical and efficient in the long run.

Safety measure to consider

In using solar energy for biodiesel storage, it is appropriate to remember the biodiesel properties for safe storage. For instance, biodiesel is a solvent that is a solvent, hydrophilic and oxidizes therefore will also react with air thus becoming unusable. The chemicals used in making biodiesel can be extremely dangerous if not handled carefully. That is why passive solar biodiesel storage is appropriate for winter environments only. For other cases, steel and plastic drums can be used for storage of biodiesel.

The advantage of using a solar shed for such purposes is that after winter, the space can be used for something different like a backyard or garage. This is a simple and effective way for storing biodiesel and definitely has no regrets. In conclusion, anyone living in cold winter regions of the world may need to put some effort into this kind of project for a stress free winter period. After all life is to be enjoyed throughout all seasons!

Improving Efficiency of Wind Turbines

2012-02-17T09:59:00.000-08:00

Wind turbines are important in the creation of energy from the wind since its speed is faster compared to other sources of energy like the solar power. It is a cheap way of getting energy as it is a renewable source of energy. This source of energy is eco-friendly as it does not produce toxic gases to the environment.

How to improve wind turbines efficiency?

Wind turbines can be improved by having simple flaps that will change in response to the change in wind. This characteristic will help greatly since the turbine blades will be characterized with the wind direction therefore the blades are in automatic control of correct steps of adjusting to the low or high winds.

In order to get optimum efficiency, it is necessary to improve wind turbines by providing information into the active control system from the sensors to avoid wind turbine break from high winds. Since wind energy is increasingly becoming the electrical power, its efficiency is very much important to identify the work load being exerted on the turbine blades consecutively to predict fatigue and avoid a breakdown of the turbines and therefore avoiding huge expenses that can be used to repair a turbine.

It is also very important to have simple but extra curved than straight blades to make it easier for the sensor records to show how greatly a blade has bent and twisted from the winds. There are some cases where the level of energy might reduce when you most need it. This is attributed to the fact that the wind speed is low, due to this, there is need to improve the efficiency of wind turbines so as to function normally at all times.

Wind speed during the day is said to be slow hence there is need to develop stable power that is generated by this energy producer. Due to this, mechanical experts are working on ways in which stable energy or power will be produced all through the day using this wind turbine irrespective of wind speed.

Another way in which you can increase wind turbine efficiency is to incorporate a concrete base. As much as this is not the best green material to use in this case, it is imperative that you use it due to several reasons;

Why concrete base?

It will cut down the number of concrete that is required to foot a tower by two thirds

They are more economical when installing
They offer faster construction times of wind turbines.
They raise the height of the wind turbine so as to increase the production of power enabling power all through the day.

You need to know that it is also possible to construct wind turbines on your own at home. In this case, you have several options of turbines to choose from such as vertical or convectional wind turbines. It is however recommended that you opt for vertical wind turbine for it is easy to construct and efficient in that it its blades are perpendicular to the ground making it easy to generate energy even if wind power is low.

With the massive climate change that is being witnessed in the entire world, there is need to take early precaution so as to avert any further problems. This is because, these changes are attributed to the fact that the activities of most people in the world do not have the best interest of the environment at heart hence great changes in the weather conditions. We need to derive best ways to produce energy without affecting the environment and the best way is to use wind turbines though we have to ensure they are efficient.

How to wire a Solar Cell into an Electrical Circuit?

2012-02-17T09:55:00.002-08:00

The role of solar cells, in other words the main parts of the solar power panels, is to absorb photons and convert them into electrons. We already know that activation of electrons produces electricity.

The electricity produced by the solar cells cannot be used directly in everyday electronic devices because of the difference in voltage. Most of the solar cells sold today have a 6V - 12V - 24V output, whereas electrical appliances function with a mains voltage requirement of 115V - 240V AC input voltage. For this very reason the energy produced by solar cells cannot be connected to any system without using an agent electronic device.

Regulation of the Voltage of Solar Cells

As mentioned above, DC (direct current) has to be converted to AC (alternating current) which is used in network structure and is convertible. The device used for this purpose is called an Inverter.

An inverter is a device that converts a direct current with a specific voltage to alternative current. In the image below you can see how voltage is converted by an Inverter.

Electrical Circuit Connection Options

1.) Direct Connection: Some home electronics need 12 - 24V DC voltage, although this is quite rare. It is possible to connect solar power panels to these devices. However, it is important to be aware that the output power solar energy cells provide is unstable. The calculations are generally done as 1000W solar power/1m2 with °90 Angle. However, this is not the case for all day. A decrease of performance and voltage occurs in early mornings and at sunset. In the diagram below you can see the amount of energy acquired depending to the angle of the sun.

In the above mentioned situation, what is required to connect the solar cells to an electronic device is to stabilize the voltage with the help of a battery, or by preparing an electronic regulation circuit. You should know that the regulation circuit cannot equalize the power while raising the voltage of the regulation circuit.

2.) With the Help of Inverter: In this phase the solar power panels are connected to the inverter module and the inverter outputs are connected to the inputs of the device that we want to use. What we have to pay attention to is that both the inverter output and device input has the same levels of voltage. There is another point you should pay attention- the drop of voltage applied to the input of the Inverter will cause a power loss as we mentioned above in the previous item. For this reason, the specific solution is to attach a battery unit to the solar panel.

The Connections of an Electric and Possible Problems

The main problem when connecting solar cells to electric circuits is voltage inconsistency. We talked about it above and offered some solutions. Now let’s move on to other possible problems and solutions.

Question: How can I connect the system without risking the solar panels if the circuit is using a different source?
Answer: In this kind of scenario you should isolate the solar cell system and the electric circuit with the help of diode. We ensure the protection of test current by connecting the solar cell’s one end to a diode and other end to the electric system. Otherwise, an inverse current would pass through to destroy the solar cells.

Question: I have a number of solar cells with different power and voltage; can I connect them all to the same electric system?
Answer: the most important thing that you should know is that you can connect two devices with different voltages in series and raise the voltage. However, you cannot do this by shunting. The basic rule of shunt is that the devices must have similar voltages. Therefore you have to connect the solar cells that have similar voltage. If you just want to raise the voltage then you can connect them in series. We will soon bring out a detailed study on this.

Question: Is there any possibility that the solar cells could harm electric circuits?
Answer: It can definitely harm the circuits. Any connection that is made recklessly or miscalculated, may harm the electric circuits.

Question: Are the variety and structure of the cables used in interconnection important?
Answer: Although not as important in smaller frames, the variety and structure of the cables are quite important in larger frames. A 200W panel, whose output voltage is 12V, has 17A output current. For this reason, the cable you chose should resist heavy currents. Imagine you are using 10 panels at the same time, in this case the output current would be around 170A and you have to choose the cable for transferring this kind of current carefully.

Dictionary of Technical Terms

Inverter: It is the device used to change AC voltage to DC voltage.
Electron: It is a particle that enables voltage generation in accordance with its speed in metals and it carries current. It moves from (+) --> (-).
Diode: It is a particle that lets electrons go over it in a one-way direction. In other words, it has (+) and (-) poles and it stops the transition of electrons.
Solar Cells: These are the most important parts of the Solar Panels. It is a chemical mechanism that converts reflected photons into electrons.

You now have the information required on how to connect solar panels to electrical circuits. In upcoming articles we will discuss series connection and shunt with illustrations.

Solar Heaters for Swimming Pools

2012-02-17T09:50:00.001-08:00

Whether fixed or portable, swimming pools can be found in the gardens of many houses throughout the world. Most people begin using their pool in the spring or beginning of summer. Although the air temperature may be pleasant enough, the temperature of the pool water is usually below desired levels at the beginning of the summer. To raise the temperature of the pool, solar heaters that use solar energy and grid tie heaters can be used.

The most important thing about solar heaters is that they are energy-saving and environment-friendly. These two terms are very important these days. The more we use renewable energy sources, the more we can help safeguard our planet's future.

There are two types of solar heaters: ones that are roof-attached and ones that are located pool side. The roof-attached solar heaters are the more commonly used.

Renewable Energy and Solar Swimming Pool Heaters

The use of renewable energy sources such as wind, solar and geothermic energy lessens the release of harmful gases in to the atmosphere and will help leave us a habitable world for future generations. Solar heaters for swimming pools may be a small solution to this problem, but they are a popular one nonetheless.

In the States, many houses with pools use this system. Thanks to this system, we can make use of the solar energy which is both cheap and clean. In this article we will try to inform you about the system's advantages in terms of energy-saving and how much we could save.

Solar Pool Heating System Parts

Solar Collector: We already mentioned about its basic function and how it works in a previous article. Briefly though, it is a component that provides the user with hot water by transferring the sunlight it absorbs to the water within it by means of a specific device. There are different sizes that can be used, depending on the size of the pool in question.

The solar collector is a device that converts the cold water it takes in into hot water; it has to different types of units: BTU and MJ.

Pump: It carries the cold water from the pool to the solar collector and carries warm water back to the pool. There many types of pumps in terms of performance, and they are chosen according to the amount of water that need circulating and the transfer rate. For larger swimming pools, pumps with greater power are obviously chosen. There are two ends to these pumps: the intake and outlet.

Filter: This helps the pool stay clean and prevents it from clogging the system by cleaning the debris before the pump takes the water to the collector. These filters should be cleaned regularly.

Check Valve (Wave): When the manual check valve is shut, the solar collectors heat the water in the swimming pool to the maximum temperature allowable and deactivate all the temperature check systems.

Flow Control Valve (Wave): The flow control valve is connected to a sensor which checks the temperature of the system and when the desired level is reached the solar panels prevent the swimming pool from getting hotter by stopping the water transfer. The check valve should always be open for this valve to function.

Sensor: This is the device that controls the Flow Control Valve in order to keep the pool temperature regulated as well as measuring the temperature on both the panels and pool.

How Solar Swimming Pool Heaters Work?

We talked about the different components and the roles they play above. Please see the picture below to understand how the system functions and how the parts are related to one another.

Let us detail the way the system functions:
1.) The solar collectors heat the water by using the sunlight. As mentioned before, the important aspect of this is transferring the heated water to the pool and taking the cool water to the collectors.
2.) The water taken from the pool by the pump is sent to the filter unit to eliminate debris.
3.) The cool water cleaned in the filter unit is directed to the solar collector by means of the pipes and simultaneously directed to a secondary pipe system which is also shunt to the collector unit. The role of the second pipe system is to protect the temperature of the pool.
4.) If the system is programmed to heat the pool, the secondary pipe system will be turned off for the water to pass through. So, the cool pool water taken from one end is heated by the collectors and unloaded as hot with the help of the pipes to the swimming pool.
5.) When the pool is warm enough, the secondary pipe system starts to pour the water to the pool by using the pipes other than the collectors. This means the water comes back to the pool without being heated. The cycle continues in this way.

Above you can see the main working principles of the solar heaters. We need to add that we turn the secondary pipe system off by manually turning the Check Wave unit off.

Installation Details

Before installing a solar swimming pool heater you should make sure you research all your options; otherwise you could encounter not only high costs, but degradation issues as well. Things to consider when researching:

1.) The Sunlight Receiving Capacity of your House: The main principle of the solar collectors is to collect solar energy and heat the water passing through. For this reason the sunlight receiving capacity of the region where your house is situated is really important. In southern regions the insulation time longer than the northern regions. Because of this, you need to define the collector and its capacity according to the region you reside.

2.) The Location of the House: If your house is located in the shadow of a hill or tall building you wouldn't be able to get constant sunlight. This is the reason why the location of the house is very important for the capacity of the system.

3.) The Location of the Collector: The solar collectors are generally located on the south side of the roof. If not, there will be degradation meaning you are not exploiting all the available solar energy.

Installation of such systems is usually carried out by professionals in the region you live, so the necessary calculations and research will be done by these people.

The capacity of the solar collector is dependent on many variables.

Pool Size: The size and depth of the pool is very important. Since large sized pools are harder to heat, a larger system should be mounted. The preferred calculation is:

Surface area of the pool / the size of the system = 1 or 2, which means the surface area of the collector should be at least the 50% of the surface area of the pool.

Average Temperature: As mentioned above, southern regions usually have higher temperature levels. So the average regional temperature is an important variable.

Pool Temperature: The desired temperature of the pool is a factor influencing the capacity is the system. For those who prefer a higher temperature, larger sized collectors that heat the pool faster is advised.

Collector Location and Tilt: We mentioned that the installation should be done on the southern side. The solar collectors are generally mounted on roofs. Sometimes they are mounted near the pool (using portable collectors). Wherever they are mounted, the collectors should be located facing south otherwise sunlight exposure would be lower and there will be degradation.

It is very important that the same collectors should face the sun. To take full advantage of the sun they should be installed with a 90 degree angle. For this reason, the panels are also mounted at a 90 degree angle.

Collector Type: Some solar collectors transform more energy as they are made from better quality material and components of a more advanced technology.

Pool Covers: It is important to install systems for preventing the energy being wasted. Pool covers are therefore an important consideration. These can be used to keep the pool warm.

10–20 % of the energy in swimming pools is lost due to the bottom and side walls. 60-70% of it is lost due to evaporation. In these cases a pool cover prevents much of the evaporation.

The evaporation rate depends on the rate of humidity, the speed of the wind and difference in temperature between the pool and environment. When you choose a pool cover therefore, consider these variables.

Energy Efficiency and Solar Pool Heaters

We have explained the main parts of the solar pool heaters and other things that you should know so far. Now, let's take a look at the performance of the solar collectors and the factors influencing the performance.

The main unit used for the solar collectors is BTU (British thermal unit). BTU = 1 pound (0.454 kg) is needed to raise the heat of the water 1 °F more. It is calculated as 1 BTU = 1055.07 Joules.

The main unit value is BTU/ft2. The higher the BTU value, the more efficient the solar collector is. For example, a solar collector having 18 BTU/ft2 value works more efficiently than a solar collector whose main unit value is 12 BTU/ft2. The advantages highly efficiency provides are:

1.) Using less space (ft2): The highly efficient collectors can absorb the same amount of energy in a smaller place.

2.) Lowering the cost: The collectors, which take up smaller places and heat more quickly, have less operating costs.

3.) Heating more quickly: The collectors with high efficiency heat more quickly in the same space.

Although high efficiency solar collectors are more expensive, they are cheaper to run in the long term.

Advantages and Disadvantages

Advantages

Heating the pool with less energy
Causing less damage to the environment by using renewable energy
A risk free heating method.

Disadvantages

Costly installation
Annual maintenance expenses
The blot on the landscape that the solar collectors cause

Frequently Asked Questions

Question: My pool is 40 ft x 45ft. What capacity should my collector system have?
Answer: The size of the area where solar collector will be mounted is defined by the efficiency of the solar collectors you would use, the insolation conditions of your house and the location of your city. If solar collectors with high or medium efficiency are used by placing them facing south and there are no high buildings and is located in a southern area:

Total pool range = 40 x 45 = 1800 square feet. If we use minimum 50% parameter, the solar collector size you have to use is:
1800 x 0.5 = 900 ft2

Question: How much does Solar Pool Water Heaters cost?
Answer: The average prices range between $2000 - $10000 and may increase according to the size of the pool.

Question: How can I calculate Price/Performance value?
Answer: There should be a note on each solar collector defining how much BTU it can produce. For example, think that each solar collector has = 30.000 BTU and think that you use 8 collectors. The total BTU value is calculated = 30.000 x 8 = 240.000 BTU/day.

If the cost of each panel is $500, 8 panels would be calculated as $4.000. Daily performance value would be Total BTU/Total Price = 240.000/4.000 = 60 BTU/day-dollar, which means you save 60 BTU/day for each day. The higher this rate is, the more advantageous you are.

Question: I would like to get a solar collector system mounted to the pool in my garden. What should I do?
Answer: You should receive quotes from experienced companies in your city. What is important when you choose the company is their experience. You should evaluate references and the terms of guarantee in your region.

Question: How long is the life expectancy of Solar Swimming Pool Heaters?
Answer: An average system has 10-25 years of use, depending on the quality of the collector.

Question: How long will it take to provide a payback?
Answer: The recycling period changes between 1- 8 years and the parts you choose have a great influence on this period.

Question: The region I live has very cold winters with ice and snow. What should I do to protect the system?
Answer: There is a method called Freeze Protection. You should set up a loop system for this system to function. The first cycle is between the collectors and heat transfer box, the second cycle is between the pool and heat transfer box. So the heat transfer occurs in the specially designed heat transfer box. The freezing temperature is lowered by pouring antifreeze to the system in the first cycle. There is no problem in the second system as there is no water.

Question: How can I install Solar Pool Heating?
Answer: You are better leaving the installation to the professionals as mounting on the roof and placing the pipes in the proper fashion, as well as all the calculations, have to be done correctly. A transfer pump is mounted between the collector on the roof and the pool, and the installation is complete after the whole system is connected altogether with the pipes.

Solar Pool Heating systems are widely used today. If you live in an area with high insolation levels, and have no high buildings around your premises, you can contribute to a cleaner environment by using solar power.

Landfill Gas Power Plants and Biomass

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Landfill gas power basically refers to the two greenhouse gases of carbon dioxide and methane. It is therefore a form of biomass used in the generation of energy whereby biomass refers to the microorganisms found in organic materials from animals and plants.

Landfill Gas Power Plant

Large produce of landfill gas plants that come from industrial and municipal waste can be used to generate electricity after the decomposing of the waste. In America where the main mean of disposal is through landfill, the waste is maintained in fairly dry and oxygen free environment but manages to generate a significant total of landfill gases with nearly 40 percent of carbon dioxide (CO2) and 60 percent of methane.

These two gases are highly explosive and if they are not fetched, they escape to the atmosphere, primarily necessitating the proposal to regulate air pollution emissions and therefore requiring the combustion and collection of landfill gases for the generation of electricity.

Landfill Gas

Landfill gas (LFG) is an important gas that can be trapped, extracted and consequently used as a safe and clean source of energy for generation of heat and electricity. During the breakdown of these waste products, there might be environmental damages and production of very unpleasant odors which in turn will lead to global warming. However, to greatly reduce the landfill emission problems, high power gas content should be used to fuel an engine resulting to a supply of electricity but the grid emissions are far much reduced.

LFG (Landfill gas) taping and production facility involves the gas pumping station that creates a space for landfill network, a flare station for the burning of unused gas in the generation of power, conditioning of the gas plant to lessen impurities in the gas engine, suitability of the pressure in the gas engine through gas compression, it is also important to install a stainless steel covering in a landfill gases engine and also includes the switching station to raise the voltage for the local power supply and generation of electricity.

The generation of gas produced by landfills may lessen the damaging environmental effects that would have otherwise led to worse situations. A landfill plant burns methane waste having roughly 23 times the harmful effect compared to CO2'that if otherwise left into the environment, would led to worse damages on the environment.

Biomass

This is a renewable source of energy that consists of living and recently living things. It is therefore common plant material that produces and generates heat. Biomass can also be used in the production of petroleum or coal where organic materials like fossil fuels are transformed by a geological process.

Biomass power is derived from different energy sources including landfill gases, wood energy which is derived from streams of wood waste and harvesting of wood directly as a fuel, waste, and garbage and alcohol fuels. The biggest source of wood is black liquor whereby the waste energy is biomass's second largest source.

Booms can be renewed to other important forms of energy such as transportation fuels like biodiesel and ethanol or methane gas. As a renewable energy, biomass can release power directly as electricity or heat or renewed into liquid biofuel. In the biochemical conversation where biomass molecules are broke down and bacteria enzymes and micro –organisms are used to crash biomass.

The environmental effect of biomass has greatly helped in the reduction of independence on oil leading to a conservation of the environment through the reduction of carbon emissiongases to the air. It is therefore important to note that, biomass as a source of energy has both the negative and positive impacts on the surroundings and in turn affect the environment in different ways.

Wind Turbine Permanent Magnet DC Motors

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Wind energy, being one of the most important renewable energy sources, and wind turbines, which are necessary for producing wind energy, are very important in today's environmentally aware world. Below we outline detailed information about generators, with many power options right up to 7 MW, as well as one of the most important components of wind turbines and motors that is used in place of generators in individually made wind turbines.

Permanent Magnet DC motors are the most important components that can be used in place of generators. The magnetic fields produced as a result of the spiral movement of the magnet within the component is that which produces electricity.

Why Use a Motor to Generate Electricity?

The most important reason is that it is cheaper than electric generators and it also contains many components we utilize in our daily lives. A motor is a device that converts electric energy into mechanical energy when electrified via its outputs; however, permanent Magnet DC motors can also have some adverse affects. The magnetic field created by the magnets causes a current to flow through a coil. You can see how electricity is produced in the below picture.

Permanent Magnet DC Motor Types for Generating Electricity

Permanent magnet DC motors are divided into two groups. The first is the permanent outer magnet and moving coil, while the second is the permanent coil and moving magnet.

Brushed DC Motor: These motors contain a permanent magnet and a moving coil within the magnet. The required electricity is produced by conveying the energy produced by the revolving brushes. Brushed DC motors are not the preferred method for producing electricity because the coil's, being in continuous motion, can have the following affects on the brushes:

a.) Degradation,
b.) Difficulty in producing electricity because of the brushes

You can see a brushed DC motor in the below;

Brushless DC Motor: These motors are the preferred choice of motors for producing electricity. Thanks to the moving magnet unit in the permanent coil, it easily produces electricity. Producing high efficiency and continuous electricity are the main features of brushless DC motors.

It is one of the most easily found motor types for those that want to build a wind generator at home. Wind energy is converted into rotation energy with the help of the blades installed on the edges of the motor and then converted into electricity with the help of the motor.

You can see images of the brushless DC motor below;

Working Principle of Brushless DC Motor

As mentioned above a magnet with two poles is rotated around a permanent coil to produce electricity.

Detailed information is given in the below picture;

Best Motor Types to Build Wind Energy Turbine

Some types of motors are more efficient than others. With the same wind speed one can produce 10W whereas the other produces 40W.

1.) Treadmill Motors: These motors are both robust and efficient. This is our top recommendation for motors for producing electric energy. You can find them easily online or in stores selling second hand products. They cost between $20 and $250. Because of its values in relation to output current and output voltage, it can easily be used as wind turbine generator.

2.) Stepper Motors: Although highly efficient, stepper motors have a lower output voltage and current than treadmill motors. It can be used in wind systems that have a lower power output.

3.) Standard Permanent Magnet Motor: These are for people who want produce electricity out of wind energy. They are cheaper than treadmill motors but some have higher HP levels. Sold for $20 - $1500, standard permanent magnet motors are our second choice for wind energy systems.

AC Motors to Generate Electricity

The most important component for producing electricity with motors is the magnet. There are no magnets in AC motors and the energy needed for the motor is provided by AC voltage.

How to Choose the Right DC Motor?

The details you need to pay attention to before you choose a DC motor for producing electricity are:

Power Selection: It is hard to rotate motors with high power capacity, therefore the wind turbine blades should be chosen in accordance to the motor power. If the area you set up the wind turbine does not have enough wind, it would be wise to use motors with 1 – 3 HP power. If the wind speed is regularly 15 Mph and over, you should use 10 HP motors.

Power Requirement: It would be better if you used a turbine that is in accordance with the need of energy of that area. The selection of motor is also important; it should be consistent with the size of the turbine. For example, if you need 2000 Whrs of power, you will need to install a 2500 Whrs system.

Blade Design: Along with the wind speed, the design of blades, which divert wind energy into rotation energy, is important. For example, the rotating speed of a 3-blade system and a 6-blade system differ from each other. Because of this, the motor you choose to use has to be in harmony with the blade design.

Motor Power: If you need 1500W energy and you use a motor that produces less than that, you could damage your motor. You should, therefore, use motors that are 30% stronger.

Wind Turbine Motor Basic Calculations

The motor you choose should be built according to variables such as wind speed, blade design, blade number, and rotor diameter. These variables in detail:

Wind Speed: Is the amount of wind passing through a specific area. It is defined by variables such as mph (mile per hour), kph (kilometer per hour), and m/s (meters/second). The wind turbines used today start to rotate with 5 mph wind speed and work efficiently between 25 and 60 mph.

Blade Design: Although wind speed is the most important factor for rotation, the blades are the main components for converting wind energy into mechanical rotation energy. For this reason the blade design is very important for efficiency.

Number of Blades: The number of blades influences the efficiency of the wind turbine. 2, 3, 5 blade wind turbines are frequently used. It is known that the more blades used, the more reliable and safe the wind turbine is. They work more silently and are more efficient. The cost is an adverse factor though.

Blade Efficiency: Is related to the blade design part we mentioned above. The more efficient the blades, the more energy produced.

Rotor Diameter: Meaning the turning diameter of the blades. More robust and big sized motors can be used in wind turbines with a high turning diameter.

TSR (tip speed ratio): If the wind turbines rotate too slowly they lose much of the wind passing over them, and if they rotate too fast it is as though they act as a wall, meaning degradation occur. For this reason, optimum tip speed ratio is very important for efficiency. Some TSR ratios are;

2 Blades: 9 – 10
3 Blades: 6 – 8
5 Blades: 4- 6

Basic Calculations: The average wind speed in your region as well as maximum wind speed must be taken into consideration before building a wind turbine. Suggested figures are:

Average Wind Speed = 25 Mph = 11 m/s
Max Wind Speed = 70 Mph = 31.4 m/s

If the region where you will build a wind turbine has a value of wind speed between the values above, you should arrange the variables like blade size and number. If you want to have 2500 W/hours, the blade length should be 1 – 1.5 meter (3 – 5 feet). The designs with 3 blades can provide 35% - 40% efficiency so we suggest 3 blade designs.

A motor which can generate 2500W power should have;

- 100A output current,
- 25V output voltage,

Or;

- 20A output current
- 125V output voltage.

For this motor to produce maximum power, it should rotate close to the maximum RPM it is intended for. For example, think that a 2500W motor’s RPM value is 1200. To acquire 2500w power in the outputs of the motor we need 1200 rpm (revolutions per minute). The lower the rpm speed, the less the output power.

Basic Power Formula;

Blade length, l = x meter
Wind speed, v = x m/sec
Air density, ρ = 1.25kg/m3
Efficient, Cp = average 0.3 – 0.4
Ptotal=0.5 (x) ρ (x) 3.14 (x) I2 (x) v3 (x) Cp

Examples

We have shown the calculations above but to make them a bit clearer there are some more examples below.

1.) Average wind speed: 35 Mph, Average Power Requirements 4500W, Blade Length =?

V = 35 Mph = 15.7 m/s
Air density, ρ = 1.25kg/m3
Efficient = 0.35
I2 = Ptotal/ (0,5*1,25*3,14*15,7*15,7*15,7*0,35)
I2= 4500/2658
I = 1.3 meter
The blade size should at least be 1.3 meters.

2.) Max RPM = 1200, Vout = 24V, Iout = 100A, Power Requirements = 1000W, Motor Speed =?

Total Motor Power = 24 * 100 = 2400 W
1200 RPM = 2400W
Each Watt = 2400/1200 = 2RPM
1000 = 2 * X
X= 500 RPM

Frequently Asked Questions

Q: What are the differences between the Permanent Magnet DC Motor and Alternator?
A: The Permanent Magnet DC Motor is used to convert electric energy into rotation energy and vice versa. The main purpose of alternators is to produce electricity and they have more production efficiency.

Q: Which is the best DC motor for electricity production?
A: Motors with a lower RPM value and high output voltage might be more efficient.

Q: What are the things that I should take into consideration when I purchase a motor?
A: The standard wind speed is 10–30 Mph, so the motor you will buy should have low RPM values. The blades connected to the motor can produce 400 – 600 RPM speed for a standard wind. For this reason a motor with a maximum 1000 RPM works inefficiently.

Q: How much voltage is required for a 12V battery?
A: To charge a standard 12V battery, 14-16V volts are needed. Make your calculations according to these values.

Q: Can you give details of a good motor?
A: Power = 1 HP, Max 300 RPM, 30 VDC, rpm/volt ratio = 10, 30A Current

Q: What brand and modal of motor would you suggest?
A: Ametek 080987K7 30VDC