Photo courtesy of kendrak at Flickr.com

Eco-conscious drivers pay a lot of attention to how much gasoline their cars use, but what about the motor oil? When cars are properly maintained, they use far more gasoline than they do oil, and driving a car requires more trips to the gas station than the service station. An unfortunate side effect is that our attention is focused on gasoline and oil isn’t something that the average driver thinks about unless there’s a problem.

Let’s say that you’ve got your ducks in a row. You’re driving a fuel efficient car and getting the best mileage possible. Even if you’re a fuel frugal hypermiler, there are still a few things you can do with your oil to reduce your car’s impact on the planet.

Oil is not a generic product – there are oils with different viscosity, oils made from different sources, and oils with more endurance than others. Here’s a good primer on the different types of oil out there. Of note:

Group IV oils… flow more freely at extreme low temperatures and don’t break down at very high temperatures. As a side benefit, they generally can be specified one or two grades lighter than a mineral oil, which consumes less energy as friction inside the engine and saves fuel.

When was the last time you changed the oil in your car? 6 months ago? 5,000 miles ago? The frequency of oil changes can have a huge impact on the environment.

On the one hand, excessive oil changes are wasteful and use up a limited natural resource. On the other hand, changing oil infrequently can cause damage to a cars engine, increasing pollution from your engine and causing additional pollution from the factory that makes replacement parts. Finding that sweet spot is important.

The majority of drivers play it safe and change their oil more than necessary. Roughly 70% of drivers surveyed changed their oil too often. This results in excessive consumption of oil, magnifies disposal problems, and hurts the pocketbooks of drivers nationwide.

A major cause of this overconsumption is the idea that cars should have their oil changed every 3,000 miles. At the service station, mechanics often put a sticker on the windshield reminding drivers to return for their next oil change in 3,000 miles. When you see that sticker, bear in mind that it was put there by someone who will make money every time you buy more oil. Consumer Reports studied taxi cabs in New York City and found that extending the interval did not affect performance or wear on the engines. They also found that oil additives had no noticeable effect on engine wear or oil endurance.

There is no catch-all rule for drivers to follow – every car has different needs and requires oil changes at different intervals. Read the owners manual for the best information about your specific car, and follow its guidelines. If the manual suggests changing the oil every 7,500 miles, changing the oil every 3,000 miles will only drain your pocket book. Many cars now have an oil change sensor that will notify you when the oil needs to be swapped out.

About half of the oil changes in America are performed by do-it-yourself mechanics. Many drivers change their own oil, or rely on a friend who knows how to change oil. There’s a problem though – few people know about the harms caused by dumping their oil down the drain or bagging it up in the garbage.

Every year, more than 300 million gallons of used motor oil are disposed of improperly. Oil that ends up in the sewer or landfill often seeps out into the water table. Just one gallon of oil can contaminate 600,000 to one million gallons of fresh water. That’s enough drinking water to supply 50 people for a year! The amount of oil in an average car can contaminate 4 acres of farmland and make it useless for a century.

This is a big problem. Less than 5% of used oil is currently recycled. The majority of used oil is burned for fuel or dumped. That’s an easily preventable waste, because there are more than 30,000 oil recycling centers nationwide!

The best way to dispose of used motor oil is to take it to a chemical disposal facility. It’s easy to find a disposal location – find an oil recycling site near you at Earth911.com. By recycling the oil, you’ll reduce the need for drilling for oil and help protect local waterways from pollution.

Photo courtesy of Spiritwood images at Flickr.com

© george for Practical Environmentalist, 2009. | Permalink | 3 comments | Add to del.icio.us
Post tags: oil

Feed enhanced by Better Feed from Ozh

Photo courtesy of AbracaDebra at Flickr.com

Everyone loves a well manicured yard, and there are a multitude of power tools that make short work of trimming, mowing, and edging. A surprising number of green options also exist, and more people are setting aside diesel powered leaf blowers in favor of lawn friendly tools.

At this minute, the majority of people use gas powered lawnmowers. It may not be a coincidence that sales of riding lawn mowers are rising along with our obesity rate. Gas powered riding mowers are the tricked-out SUVs of lawncare. The average lawnmower uses only 0.5 gallons of gasoline per hour, but self propelled mowers can use 200-300% as much fuel while delivering only a fraction of the exercise.

Even gas mowers that have to be pushed produce a lot of pollution. They emit approximately 11 times as much pollution per hour as a car. Most of this pollution is in the form of volatile organic compounds that can cause cancer and trigger asthma attacks. Lawnmowers emit nitrogen oxide, carbon monoxide, and other harmful hydrocarbon compounds. After they settle on the yard or filter into local rivers and streams, these toxins work their way into our food and drinking water.

Most of this pollution could be avoided if the lawnmowers had catalytic converters, but very few lawn mowers include even rudimentary pollution controls. Some of the worst lawnmowers have 2 stroke engines. This older technology relies on lubricant mixed with gasoline in the fuel tank. This mixture of fuel and oil eliminates the need for a dedicated lubricating system, which makes 2 stroke engines weigh less. Since 2 stroke engines have fewer components, they are also cheaper to build. Unfortunately, these costs savings have an environmental cost. 2 stroke engines burn oil along with their fuel supply and put out far worse fumes than 4 stroke engines or electric drive trains.

Do you want to breathe diesel fumes or poison your yard with partially burned gasoline? There are much better, greener options out there. Some alternatives to gasoline powered mowers include natural gas mowers, electric mowers, push reel mowers, livestock, and even using native plants for landscaping.

Photo courtesy of cheryl at Flickr.com

Fuel alternatives for gas lawnmowers
Unleaded gasoline is one of the most popular fuels for lawnmowers, but mowers also exist that are designed to burn other compounds. Some mowers can be converted to use cleaner fuels. Check with the manufacturer – not all leaf blowers, edgers, and lawn mowers can burn ethanol or bio diesel. Other models are made specifically to burn methanol, propane, or methane. These alternative fuels still produce pollution, but they produce far less (especially if you have a local fuel source with a lower associated carbon footprint).

Photo courtesy of jgoverly at Flickr.com

Electrical mowers

Electric mowers come in two varieties – battery powered mowers and plug-in mowers. If you want freedom from cords, battery mowers are the way to go. They have some drawbacks though, including limited endurance, reduced torque, and increased weight. Mowers with batteries are also less eco-friendly than plug in mowers. Manufacturing batteries is a dirty business, and batteries also waste a lot of power while charging up (20-80% depending on the type and age of the battery).

If you’re using an electric lawn mower, the source of electricity at your home determines the footprint of the mower. More than 80% of the power on the US power grid comes from coal, and that power is only slightly cleaner than gasoline. If your home is supplied with green electricity from solar arrays, wind turbines, a hydroelectric dam, or similar sources, then a plug-in lawnmower is much cleaner. You can get even more green out of an electric mower by converting it to run on solar power.

Photo courtesy of M.Barkley at Flickr.com

Push reel mowers
People powered lawnmowers are even more environmentally friendly than electric mowers, because they’re powered by human muscle power. Rather than burn calories on an endless climb on the stairmaster, why not use your muscles to accomplish something? Manual mowers have several advantages – they produce no exhaust fumes, they don’t ever need to be plugged in, and they are far less dangerous than other mowers. Even if you run the mower over pebbles, the slow moving blades aren’t going to throw rocks.

Push reel lawnmowers are pleasant to operate. Since they have no engine, they are almost completely silent. You can listen to birds in the trees while mowing, or bring your phone along and talk to friends while doing lawncare. If you’re an early riser, you can mow at 7am without waking up your neighbors.

Photo courtesy of Beaker’s Glassworks, Jewelery & Things at Flickr.com

Lawn mowing animals
If pushing a mower (of any kind) isn’t your idea of fun, you could always outsource the work. Livestock is nature’s own solution to overgrown grass. If you’ve always wanted your own full-time gardener, don’t forget that ruminants make a really cheap labor force.

Sheep and geese are happy to trim the yard, and they produce wool and down feathers as well as meat. Sheep ranchers are having a tough time with falling prices, and some are making ends meet by leasing out their sheep herds as expert mowers. If you have a larger area, cows are four legged mowing machines. In Australia, wallabies are becoming increasingly popular for their lawnmowing skills.

Some towns and HOAs have started keeping herds of farm animals instead of sheds full of gardening equipment. On the Google campus, a trial is underway using goats to keep the lawn trimmed. Several urban homesteaders have reported problems with goats though, because they’re escape artists and they can be unpredictable eaters. That means that they’ll eat some weeds while ignoring the grass, or that they’ll chew one area down to the roots while ignoring thigh high blades of grass on the other side of the yard.

Photo courtesy of albatrail at Flickr.com

Slow growing / native plants
Another way to control your landscape is to use alternative plants. Some species of grass grow at a much slower rate than the popular St. Augustine and Bermuda. These slow growing grasses require less maintenance, and they often require less fertilizer (further reducing their environmental impact). Clover and bluebonnets are popular alternatives because they naturally fertilizes the soil.

When choosing plants, think about using native species. Native plants are very well suited to the climate and wont run out of control like invasive plants. Xeriscaping your yard will also reduce the amount of water needed to keep the landscape lush and green in the middle of summer. Cactus and wildflowers aren’t the only native plants to consider – moss works surprisingly well and prairie grass also has great eye appeal.

Photo courtesy of one2c900d at Flickr.com

© george for Practical Environmentalist, 2009. | Permalink | One comment | Add to del.icio.us
Post tags:

Feed enhanced by Better Feed from Ozh

Photo courtesy of Army.mil at Flickr.com

When you think of environmentally friendly groups, Greenpeace, REI, the Sierra Club, New Belgium Brewery, and Seventh Generation are some of the green companies and organizations that are likely to come to mind. But what about the US military?

The armed forces are surprisingly green. For example, the Air Force is the third largest buyer of alternative energy in the US. The US Army is also rapidly seeking energy alternatives. Officers are trying to adopt solar, wind, and bio-diesel energy sources to reduce logistics problems and conserve resources:

The effort will have to be really serious, as their energy costs have increased a full 40% during the last seven years, even while they have cut consumption by almost 8%. According to their latest numbers released this week in Washington, D.C., right now they are spending $2 billion on fuel every year.

Reducing energy use in Iraq and Afghanistan is a top priority. By reducing the need for fuel convoys, energy efficiency reduces exposure to IEDs. It also protects soldiers from toxic emissions that come along with diesel generators. In recent years, the focus on energy conservation has really started to pay off.

That’s all well and good, but helping the environment is clearly a fringe benefit for most military planners. There are signs that a green culture is growing within the armed forces though. Several branches of the military are working to reduce the use of toxic chemicals in everything from paint and electronics to fuel and explosives. For example, the US Navy is testing lead-free bullets.

If these bismuth alloy bullets perform as expected, there’s a good chance that shooting ranges will soon be lead free. Cleaning up lead is a huge expense, and lead dust is a major health danger that affects cleaning crews at every gun range. Also, lead can leak into groundwater from outdoor berms and harm the environment.

In recent years, environmental activists have also been successful in forcing the military to adopt several earth friendly policies. Protesters are increasingly likely to raise environmental issues. While the supreme court rejected arguments against the use of high intensity sonar, other efforts have resulted in legislation prohibiting sewage release in the ocean and disposal of toxic paints in furnaces. Due to environmental concerns, the US Marines are currently looking for eco-friendly ways to dispose of toxic ordinance and recycling mothballed equipment.

Photo courtesy of ScottPartee at Flickr.com

Activists are crucial to enacting change – just look at Vieques. Vieques is a small island in Puerto Rico and the area was used as a naval firing range for most of the 20th century. After decades of public outcry, the Navy was forced to stop using Vieques as an ordinance testing ground.

There is a surprising twist to the story. Due to the Navy’s use of the island, Vieques has higher biodiversity than many surrounding areas. The firing range prevented development while most of the Caribbean was covered in resorts and boardwalks. Believe it or not, firing high explosive at wildlife is less destructive than building permanent structures. As a result, Vieques is currently booming as an eco-tourist destination.

The military still has quite a ways to go, but there are encouraging signs that the armed forces are becoming much better stewards of the planet.

Photo courtesy of Brent and MariLynn at Flickr.com

© george for Practical Environmentalist, 2009. | Permalink | No comment | Add to del.icio.us
Post tags:

Feed enhanced by Better Feed from Ozh

Photo courtesy of London Permaculture

Under new Federal laws, you can get tax credits for 30% of most solar panel installations. Some states have additional incentives, and many utilities are also encouraging customers to install solar panels so that they don’t have to build new coal power plants.

Even with these incentives, photovoltaic panels are pricey. In these tough economic times, it’s important to remember that there are many other ways to take advantage of energy from the sun. Here are a few low-cost options:

Install a solar water heater – Passive solar systems cost a fraction of what solar panels cost and they are much more efficient at heating water (because they generate heat directly, without the need for inverters or battery storage of energy). Solar water heaters are also eligible for a 30% tax credit, the same amount that photovoltaic panels can earn. There are many different designs for solar water heaters, and some are more suitable for different parts of the country.

Use a clothesline – For the cost of a sturdy rope and some clothespins, you can unplug your electric clothes dryer. Even on a cool day, a gentle breeze will suck the moisture out of clothes. Clothes that are dried on a clothesline last longer (there’s less wear and tear from tumbling in the dryer), they smell better, and they’re naturally sterilized by UV light from the sun. Switching to a clothesline can cut your electric bill by 10-15%.

Turn out the lights – When the sun is shining, there’s no reason to keep the curtains closed. Instead of using a couple of hundred watts of electricity to power lightbulbs, turn off those lights and let the sunlight in! If Peeping Toms are a worry in your neighborhood, install slats or polarized window coverings for privacy. These window treatments will also filter out UV light and reduce carpet fading. Or, you can plant a window box full of kitchen herbs and obscure the view with tall plants while still letting in natural light.

Build to take advantage of the sun – When drawing blueprints or choosing a place to live, remember that a building’s layout can make a major difference in the amount of air conditioning and heating that’s needed. One thing to consider is orientation – building short walls on the east and west sides reduces the surface area that’s exposed to early morning and late evening sunlight. Another thing to consider is solar massing – using thick, heat absorbent materials like adobe can insulate a building against hot weather during the day and cold weather during the night, cutting heating costs by up to 65%.

Use trees – Trees provide wonderful natural shade, and they also capture solar energy the old fashioned way, by converting sunshine into firewood. Tree choices can also complement the way that buildings capture sunlight in the winter and block sunlight in the summer. One popular landscaping choice is to plant deciduous trees on the east and west sides of a building. That way, the leafy trees block sunlight in the summer (when leaves are full) and let sunlight through in the winter (after the leaves fall off).

Try a solar cooker – Sunlight is a great way to boil water and cook food. It’s easy to focus sunshine with collectors, and simple solar cookers can be made for less than $15 using just about anything and aluminum foil. Here are instructions for making a solar cooker out of a used pizza box. There are compact solar cookers tailor made for camping and larger models suitable for crock pot cooking.

In many developing countries and off-grid locations, solar cookers are reducing indoor air pollution by replacing firewood, charcoal, propane, and other fuel sources. These solar cookers can save thousands of lives each year, while also reducing deforestation and reducing conflict over limited resources. Since sunlight is free, solar cookers drastically cut the cost of boiling water for sanitation purposes. If you want to take advantage of sunlight without buying a solar panel, here’s a great recipe for Solar Baked Brownies!

Photo courtesy of AIDG

© george for Practical Environmentalist, 2009. | Permalink | 2 comments | Add to del.icio.us
Post tags: laundry, sanitation, solar, water

Feed enhanced by Better Feed from Ozh

Photo courtesy of WallyG at Flickr.com

Here at the Practical Environmentalist, we’re green news junkies. We keep an eagle eye out for the latest science, social, and environmental developments and try to sum up the big picture. A lot of exciting things are going on right now, with recent legislation leading the way.

Many gardeners, ranchers, and farmers are concerned about a Food Safety Bill that’s pending in the House. There have been rumors that this legislation would redefine the word “organic”, or outlaw small scale farms, or make it impossible to grow heirloom seeds, or drive up the price of locally grown food. HR 875 has been the subject of message board arguments, blog punditry, and even chain mail. Before you call your Congressman and voice concerns, it’s important to do some fact checking about HR 875.

There’s also some interesting news about ethanol and biofuels production. The percentage of ethanol in gasoline is currently capped at 10% (E10), but Ag Secretary Vilsak is urging lawmakers to raise the amount of ethanol that’s allowed in transportation fuel. He’s calling for E12 gasoline, and we may see 15-20% ratios if the Environmental Protection Agency approves E15 or E20 gasoline. This move face opposition from equipment manufacturers who are worried that high ethanol blends may harm engines. Lawnmower and boat engines are particularly at risk.

Several states are making green news too. Michigan is offering scholarships to train unemployed and underemployed workers for green collar jobs – these Michigan Promise scholarships may help the state survive waves of layoffs in the automotive sector. The funds come from Tobacco settlements and are not at risk from the declining tax base in the state.

Illinois, California, Texas and other states are rushing to build transmission lines that will carry wind generated electricity from the countryside into the big city. A recently proposed line called the Green Power Express would run from the Dakotas into Chicago. This is one of many infrastructure projects that could pay dividends in reducing pollution and reducing dependence on foreign energy sources at the same time.

Private enterprise is also partnering with city and state governments to encourage energy saving projects. “Green Mortgage” programs allow homeowners to take advantage of the tax break on mortgage interest to finance energy saving additions and renovations to their homes. These programs will funnel money towards installing insulation and energy efficient windows, or replacing light bulbs with skylights and upgrading Energy Star appliances. In the process, they will generate manufacturing and construction jobs now while boosting energy efficiency of homes for decades to come.

Do you know of any other big green news? Feel free to share in the comments section below!

© george for Practical Environmentalist, 2009. | Permalink | No comment | Add to del.icio.us
Post tags: ethanol, news, organic

Feed enhanced by Better Feed from Ozh

Photo courtesy of Saw You On The Flipside

For some people, travel is an unpleasant necessity. They travel to meet clients or commute. For other people, travel is a joy and the reason that they work. They save up money for vacations and sight seeing. Whether you’re in a hurry to get home or if you’re taking the chance to satisfy your wanderlust, there are plenty of opportunities to add some green to your itinerary.

From hiking boots to luxury jets, we have more transportation options today than ever before. Most travelers weigh these options based on comfort, price, and time. Yet an increasing number of adventurers and businesswomen are factoring in the environmental impact before they buy tickets.

When choosing transportation with a small carbon footprint, it’s important to compare apples to apples. One way to compare the environmental impact is using passenger miles. Passenger miles are calculated by taking the total fuel consumed and dividing by the number of passengers. For example, consider a car that gets 40 miles per gallon. If the driver is the only person in the car, then the driver is responsible for 19.4 pounds of CO2 for every 40 miles driven or 0.485 pounds per mile (19.4 / 40).

If we add a passenger with heavy bags, the car’s MPG will decrease slightly to about 39 MPG, but the amount of carbon dioxide generated will stay roughly the same. That footprint is spread out over 2 people instead of one. (19.4 / 2) / 39 = 0.249 pounds per mile. This is because so much of the energy used in moving a car is used to move the car itself.

In short, vehicles that travel full are more fuel efficient than empty vehicles, and passenger load can greatly affect the pollution produced per person. While trains are often more carbon efficient than buses, a fully loaded passenger bus may even be more efficient than a train. Then again, rail systems in some countries have the edge.

The most common way to compare different fuel sources is to use Miles Per Gallon equivalence (MPGe), but some fuel sources are dirtier than others. For example, generating 100,000 British Thermal Units (BTU) from coal will produce about 42 lbs of CO2, while natural gas will produce the same amount of energy while emitting about 14 lbs of CO2. So, a coal powered train may be more energy efficient than a natural gas powered bus, but it would produce more pollution to travel the same distance. Hard numbers for this “pollution efficiency” are difficult to pin down.

And that’s not all… some situations can magnify the effect of emissions. For example, pollution from airplanes is released in the upper atmosphere. Carbon dioxide, nitrogen oxide, water vapor and other byproducts behave differently in the upper atmosphere than they do at ground level, multiplying their effects. For more information on this subject, look at how various scientists calculate the radiative forcing factor. As a rule of thumb, each pound of airplane emissions is about 2.8 times worse than emissions from other forms of transportation.

From lowest impact to highest impact, here is a rough guide to transportation options (including some data from the US Department of Energy Transportation Energy Data Book and manufacturer’s sites):

On foot / Walking
Bicycle
Horseback Riding
Rickshaw
Electric Motorcycle / Scooter
Vanpool or Shuttle (1,322 BTU per passenger mile)
Motorcycle (1,855 BTU per passenger mile)
Train (2,816 BTU per passenger mile)
Ultra Efficient Passenger Car (ie; a Prius)
Average Passenger Car (3,512 BTU per passenger mile)
Passenger Trucks/SUVs (3,944 BTU per passenger mile)
Bus (4,235 BTU per passenger mile)
Turboprop Passenger Plane (for short distances)
Fuel Efficient Passenger Jet (for long distances)
Piston Engine Passenger Plane
Older Passenger Jets
Small Prop Plane (ie; Van’s Aircraft’s RV-7: ~36 MPGe per passenger at full capacity)
Ferryboat
Helicopter (~20 MPGe per passenger at full capacity)
Cruise Ship (~17 MPGe per passenger at full capacity)
Motorboat (~15 MPGe per passenger at full capacity)
Jet Ski (~10 MPGe per passenger at full capacity)
Executive Jet (~0.8-5 MPGe per passenger at full capacity)

Are there any transportation methods that I’m missing? It’s hard to quantify the MPGe for a hang glider, sailboat, submarine, electric pogo stick, or jet pack, but if you have the scoop on how to rank an unusual form of locomotion, please drop a note in the comments at the bottom of this page.

So, how can you use this list? Before you book a trip or reserve a hotel room, make sure to check out all of the options that are available. Instead of flying cross country, do you have time to take the train? Instead of staying at a hotel across town from a conference, can you find a hotel within walking distance and skip the rental car?

A few more tips for carbon efficient travel…

Often, the green choice will yield a more pleasant trip and save money at the same time!

Photo courtesy of svanes

© george for Practical Environmentalist, 2009. | Permalink | No comment | Add to del.icio.us
Post tags: amtrak, bicycle, bus, car, carbon, carpool, gas, oil, parking, Train

Feed enhanced by Better Feed from Ozh

Photo courtesy of Shira Golding

Earth Day has come and gone, but there are still a lot of contests going on that focus on environmentally friendly ideas. If you have green skills or an innovative idea, here are some fun contests that offer a chance to keep changing the world:

Show Us Your Green Contest from Threadless T-Shirts:
Prize: $3813.74 (and growing as more people participate)
Method of entry: Digital Picture on Flickr or Tweetpic along with a typed description on Tweet
Deadline: April 27, 2009

Spring Dream Challenge from Lowes
Prize: $301-2672 (different prize packs based on the entry category)
Method of entry: YouTube video
Deadline: May 3, 2009

Escape to Alaska or Bust Contest from Alaska Wildland Adventures
Prize: 8 Day / 7 Night Lodge stay with a wildlife expedition
Method of entry: Up to 33,000 characters in essay format
Deadline: May 22, 2009

The Green Effect Contest by Frito Lay’s SunChips & National Geographic
Prize: $20,000 to spend on a green cause
Method of entry: 100-250 word proposal for improve the environment, with up to 4 pictures in support and up to 3 minutes of video explanation
Deadline: June 8, 2009

© george for Practical Environmentalist, 2009. | Permalink | No comment | Add to del.icio.us
Post tags: contest

Feed enhanced by Better Feed from Ozh

Photo courtesy of Vagawi

Every year, approximately 1 Billion tires are replaced due to wear and tear. Many of these tires end up in landfills, but the majority are burned or converted into Tire Derived Fuel. A growing number of tires are being recycled after they have reached the end of their useful lifespan.

Recycling tires is a tricky process, because tires are a hodgepodge of many different things:

A typical passenger tire contains 30 types of synthetic rubber, eight types of natural rubber, eight types of carbon black, steel cord, polyester, nylon, steel bead wire, silica and 40 different kinds of chemicals, waxes, oils and pigments. They typically contain 85% hydrocarbon, 10-15% iron (in the bead wire and steel belts) and a variety of chemical components.

Discarded tires are mostly inert, but their effects on the environment are largely unknown. When discarded in landfills, they pose a significant fire risk and they take up a lot of space. Even before they reach the landfill, a lot of tire rubber flakes off into the environment from normal wear and tear. The effects of this worn tire rubber haven’t been widely studied.

Old tires are a cheap and plentiful resource, so many different ideas have been proposed to put old tyres to practical use. In the 1970’s, several attempts were made to build artificial reefs out of discarded tyres. Those plans didn’t work out very well, because chemicals in the tires repelled marine life. Now, millions of tires are rolling around on the ocean floor and even causing damage to natural coral reefs.

More recently, tire recycling companies stepped in and found commercial uses for tire scraps. More than 80% of dead tires end up getting turned into Tyre Derived Fuel. When tires are burned along with coal and wood scraps, they can actually reduce emissions of some pollutants.

There are other uses for recycled tires – they’re used as an ingredient in road construction, as a replacement for pavement, to make rubber flooring, and as artificial mulch. A blend of liquid asphalt and “Fine Grind” tire rubber lasts about 25% longer than other road surfaces, which cuts down on maintenance costs for highways nationwide. Crumb rubber is also widely used on running tracks and playgrounds for children. It provides excellent cushioning and prevents injuries for children and adults alike. Rubber chips are also offered as mulch.

Rubber mulch is a controversial product. Some gardeners swear by it as a long lasting weed suppressant and low maintenance landscape surface. Other gardeners steer clear of rubber mulch, due to concerns about chemical leaching, fire hazards, and smell.

Here are some of the benefits of using rubber mulch instead of wood mulch:

Here are some of the problems with rubber mulch:

The jury’s still out, but recycled rubber mulch seems safe to use in certain applications. What do you think? Do you have any experience using rubber mulch in your garden or greenhouse?

Here’s another way you might want to consider to recycle old tires – they make great insulation for earth friendly homes. Crumb rubber also shows promise as a water filtering medium. In Arizona, state law makers are exploring another way to dispose of old tires: filling abandoned mine shafts to eliminate dangerous pitfalls. A few million years from now, who knows – those mine shafts might fill up with black gold!

Photo courtesy of Road Dog

© george for Practical Environmentalist, 2009. | Permalink | One comment | Add to del.icio.us
Post tags: recycled tires, recycling, tire, trash

Feed enhanced by Better Feed from Ozh

Photo courtesy of AIDG

If you hang out with gardening hippies, you may hear the term “aquaponics” thrown around. So, what the heck does it mean?

Aquaponics is a gardening technique designed to maximize water efficiency and minimize the need for fertilizers. The technique involves farming and raising fish in an integrated system, where fish produce natural fertilizer while plants filter and oxygenate the water. A well designed aquaponic system requires minimal supervision and creates two desirable crops – fresh herbs and fish. The components of the system produce synergy: fish and plants grow more efficiently together than they would in separate tanks.

…when the aquaponic system is fully operational after six months, it leaps ahead of inorganic hydroponics. This leads to earlier maturity of greenhouse crops under aquaponics and much heavier cropping.

Aquaponics is a portmanteau of the words Aquaculture and Hydroponics. It gets improved results due to the symbiotic behavior of several living organisms. The plants and fish complement each other, but a lot of the productivity depends on integrating bacteria and microorganisms in the system. Bacteria convert fish waste into useful nutrients for the plants, and phytoplankton produce food for the fish.

Aquaponics is an old concept – the ancient Aztecs and Egyptians used the technique with various plant and fish species. In China and Thailand, it’s traditional to raise fish in flooded rice paddies. Since the 1970’s, several universities have been developing modern techniques and applying scientific method to get the greatest performance.

Compared to conventional agriculture, aquaponics is a huge water saver. On a farm in Oklahoma, it takes 6 gallons of water to grow a head of lettuce. At 24 heads per case, that means raising 1,250 cases of lettuce using conventional methods would require 180,000 gallons of water. A DeepWater aquaponic system uses about 16.1% as much water to create the same results (and it generates more than 3,600 pounds of fish fillets and 7,400 pounds of fish scraps for use as fish feed or fertilizer).

Here’s some more information on aquaponic water efficiency, comparing aquaponics to hydroponics and conventional farming techniques:

Estimated total value of output is then A$405,000 ($305,491 USD) — which represents water use efficiency of around 173 liters/A$100 of production.

This compares very favorably with the Australian commercial hydroponics figure of 600 liters of water used per A$100 of production.

There are many different aquaponic systems, but two major schools have emerged. These two approaches look very different, and each is best for certain crops or locations. These competing systems are Deep Water Aquaponics and Reciprocating Aquaponics. The primary difference is where the plants are positioned. In Deep Water Aquaponics, plants float on top of a pond of water (usually inside styrofoam rafts with holes for their roots). In Reciprocating Aquaponic systems, the plants are outside the pond and water is carried to their roots along irrigation tubes.

Photo courtesy of Aria Fotografia at Flickr.com

Deep Water Aquaponics is also known as Raft Culture Hydroponics or “the UVI system”. One of the main proponents of this type of hydroponics is Dr. James Rakocy of the University of the Virgin Islands. He offers training courses and maintains an aquaponic demonstration facility with 15 full scale systems that have been in continuous operation for several years. The system is very productive and water efficient:

UVI’s aquaponics system, which occupies an eighth of an acre and uses 29,000 gallons of water, can produce annually 11,000 pounds of tilapia and 11,000 pounds of basil or 1,250 cases of lettuce.

Here’s a cool photo-tour of the UVI system. Note – the fish are grown in separate tanks to prevent them from eating the roots of crop plants.

Reciprocating Aquaponics is also known as “Flood and Drain” or “Ebb and Flow”. This system uses gravel or sand beds to filter water from fish tanks, and then irrigates plant beds using irrigation pipes (or positions plant roots inside the irrigation pipes). The result is a system with more control over temperature and humidity. Some plants that don’t do well in hydroponic systems thrive in these conditions, because their roots are protected against rotting. Biofiltration beds also allow more microbial activity in a smaller area, which is important when space is limited. On the flip side, the filtering media will get clogged over time, and cleaning it is hard work.

This type of aquaponic system was developed by Mark McMurtry and many other pioneers. Several different ebb and flow systems have been built since the mid 1980’s.

If you’re looking for a cool way to renovate the pool in your back yard, or if you want to do more with the rain water in your rainbarrels, there’s no time like the present to check out an aquaponic system.

Photo courtesy of ideonexus at Flickr.com

© george for Practical Environmentalist, 2009. | Permalink | No comment | Add to del.icio.us
Post tags:

Feed enhanced by Better Feed from Ozh

Photo courtesy of Earth Hour Global at Flickr.com.

Once a year, environmentalists around the world turn out the lights for an hour. This year, Earth Hour falls on Saturday, March 28th, and many different homes, offices, and government buildings are taking part. The organizers of Earth Hour hope to raise awareness of how much energy we waste with inefficient lighting systems. For one hour a year, everyone can take part and see the beauty of the natural sky that’s lost due to light pollution.

The World Wildlife Fund and other environmental organizations are hard at work planning activities for Earth Hour 2009, ranging from star watching and recycling events to tree plantings and slumber parties. Find an Earth Hour event nearby, or if there aren’t any, you can plan one yourself with help from the Earth Hour Facebook group!

Now’s the time to raise your voice and take part. Are businesses and government offices in your town participating in Earth Hour? Check the latest Earth Hour news, and if City Hall isn’t taking part, now is a good time to ask pointed questions of your elected officials. While they’re on the line, why not ask about steps that the city is taking to retrofit energy efficient devices into public buildings and legislation that improves local air quality?

Maybe it’s time to re-evaluate how we destroy the night sky for the other 8,765 hours of the year…

Photo courtesy of fyngyrz at Flickr.com.

© george for Practical Environmentalist, 2009. | Permalink | No comment | Add to del.icio.us
Post tags: carbon, earth hour, WWF

Feed enhanced by Better Feed from Ozh