February 25, 2011
(Image Credit: Creative Commons photo by eutrophication&hypoxia)
Energy from coal might seem cheap on the surface, but when you add in the costs of coal-related pollution and health issues, the true cost of coal starts looking pretty steep.
Coal-fired power plants spew toxins into our air while mountaintop removal mining practices destroy our mountains and pollute surrounding waterways. Here are just a few of the hidden annual costs of coal from the Appalachian region alone, according to a recent Harvard Medical School study:
- Public health: $75 billion
- Health costs due to air pollution from coal power plants: $187 billion
- Mercury emissions: $29 billion
- Climate change and greenhouse gas emissions: $206 billion
According to the study, adding up all of these hidden costs would increase the per kWh price for coal by almost 18 cents. To put that in perspective, coal power now costs around 12 cents per kWh. Solar power costs between 10 and 15 cents per kWh.
Almost 40 percent of our energy supply here in the U.S. comes from coal, so just using less power is one way to reduce the coal you consume. If you can, switching some or all of your home’s power supply to alternative energy is amazing. For folks who can’t afford the investment to get that going, there are other ways you can reduce your coal dependence.
Cutting back on vampire power by using a smart power strip and remembering to unplug unused chargers can go a long way toward saving energy and reducing your coal use. In the warmer months air conditioning is the largest power suck in many homes, so try to take some simple measures to cool your home without the air conditioner.
It also might be time to take a look at your electronics and appliances. From your washer and dryer to your TV and gaming consoles, opting for efficiency can make a big difference in energy savings.
- Top 10 Coal-Burning Countries
- Clean Coal’s Dirty Secret
- Are You Wasting Electricity? Probably More Than You Think
February 24, 2011
Cement is one of the most significant single sources for carbon emissions, due to the intense energy required for its production and the volumes of it that are produced annually, as well as from material itself, but an alternative is now available. It doesn't just reduce the amount of carbon dioxide emitted, it actually binds more CO2 than is emitted from its production, which makes its production carbon negative.
Novacem has developed a new cement that uses magnesium silicate instead of calcium compounds. The new material is supposed to have performance and cost comparable to ordinary Portland cement. Furthermore, because the production of magnesium silicate is a lower energy process, it can be manufactured using biofuel, instead of requiring more intensive and polluting energy sources.
The company also notes that "production of our cement is carbon negative; more carbon dioxide (CO2) is absorbed during the process than is emitted." Manufacturing a tonne of this cement results in the absorption of up to 100 kg (220 lbs) of carbon dioxide more than is emitted in the process.
Magnesium oxide is widely available as well, so there should not be an issue of material scarcity with the use of this as a Portland cement replacement. The company is not producing the material itself, but is instead seeking to license its technology to producers.
via: Jetson GreenPrint This Post
February 23, 2011
Home improvement warehouse stores are full of gadgets and devices aimed at easing your gardening work. However, many successful home gardens are cultivated with a handful of good hand tools — and the high-tech alternatives often won’t help you grow a tastier tomato or brighter begonias.
A gardener’s toolkit requires little more than a trowel, fork, manual weeder, rake, and shears. Each time-tested tool beats several high-tech alternatives.
1. Shears: A good pair of bypass pruning shears can keep many trees and shrubs neat and tidy, while also helping harvest vegetables and flowers, clear away dead leaves and cut weeds away from the plants you want to keep.
Power pruners such as the Alligator Lopper add chainsaw teeth and electric scissor action. They may seem like a great idea, but sharp hand pruners are plenty powerful for most home gardeners. The Alligator Lopper may be more hazard than help in many homes.
Another overrated alternative is the Garden Groom collecting electric hedge trimmer. It looks like an oversized high-tech iron, and it trims away hedges, then shreds and collects the leaves all in one device. However, users complain it is too heavy and may not do the job. It only cuts a small amount at a time, so it requires several passes on many hedges. It also doesn’t pick up all the debris.
2. Rake: Garden vacuums — either gas- or electric-powered — are popular among people anxious to keep a perfect yard. They suck up leaves and dirt, but that is the problem — dirt belongs in the yard. Instead consider raking the leaves and other debris, or simply leaving many of them where they fall.
This can create healthy mulch or compost and you don’t have to send all those bags of vacuumed leaves to the landfill.Print This Post