Methods for Improving Energy Efficiency
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This is an article dedicated to sharing information based on improving the efficiency with which we use the worlds available energy. Improving the energy efficiency in aspects such as our homes/buildings, and transportation; and finding new, more efficient energy sources will lead towards a more sustainable and ecologically friendly future.
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Efficiency in Homes/Buildings
Energy Audits
The easiest way to improve the energy efficiency of a building is to do an energy audit, or better yet have the building audited by a professional. There are some things you can do yourself such as repairing drafts around windows and doors. But many other inefficiecies can be found with the tools and knowledge used in an energy audit done by a professional. Here are a couple of the tests done in a professional energy audit:
- Blower Door Test- This test determines whether there are any leaks in your house. Drafts in doors, windows, and leaks in the ducting and ventilation systems can be found and repaired.
http://www.eere.energy.gov/consumer/your_home/energy_audits/index.cfm/mytopic=11190
- Thermographic Scan- Using infrared cameras the auditor can find leaks in windows, doors, and ventilation, as well as inadequate insulation and electrical issues.
http://www.eere.energy.gov/consumer/your_home/energy_audits/index.cfm/mytopic=11200
- Perfluorocarbon Tracer Gas Technique(PFT)- Created by The Brookhaven National Laboratory, the test measures, over a certain period of time, the change in concentration of a perfluorocarbon gas to determine the leakage in the building. This is different from the blower test in the way that the building is not depressurized by a fan. Instead it measures the leakage at a more natural setting.
http://www.eere.energy.gov/consumer/your_home/energy_audits/index.cfm/mytopic=11210
Other Methods
Improvements can also be made on the exterior to better the efficiency of a building. Here are some of the simple methods recommended by "green" building professionals:
- Passive Lighting/ Daylighting- By placing windows on the south side of your building you can optimize incoming sunlight which decreases your dependence on artificial lighting.
- Passive Temperature Control- As with the lighting, the southfacing windows provide heat from the sunlight during winter. Properly placed windows and roof overhangs provide warmth and light during the winter, and cooling and shade during the summer. There are many other techniques as well. Here are a few:
- Paint and Roofing- Selecting light colors for paint and roofing material will reduce the heat entering your house from the sun during the summer.
- Mounding- Dirt mounded around the base of the house can provide further insulation and cooling during the summer.
- Thermal Barrier- A heat barrier can be created by planting shrubs and bushes near the house. This barrier helps to hold heat in during winter months and provides shade and cooling during the summer.
- Build a Pond- Build a pond to cool the breeze before it reaches the house.
- For more exterior techniques visit:
http://www.austinenergy.com/Energy%20Efficiency/Programs/Green%20Building/Sourcebook/energy.htm http://www.seco.cpa.state.tx.us/re_sustain_info.htm
Making these improvements will better the efficiency of the building dramatically, and in doing so reduce the amount of energy needed to live comfortably, saving money and reducing the carbon footprint of the building.
Efficiency in Transportation
Some major topics of debate lately are the issues surrounding fossil fuels and the effects on our environment due to the burning of those fuels. Not only is the carbon output into the atmosphere becoming a massive problem, but the amount of energy input for using fossil fuel derived fuels is greater than the energy output, making fossil fuels an inefficient and wasteful fuel for transportation. While research is being done on many alternative fuels such as hydrogen and compressed air, biofuels are the method getting the most attention. Significant advances have been made in ethanol fuels, as well as in biodiesel.
Biodiesel
Biodiesel is a fuel made of vegeatable oils or animal fats, combined with an alcohol(methanol or ethanol) and a catalyst(NaOH or KOH). The byproduct of this reaction is glycerin and methyl/ethyl esters(biodiesel). In a study by the US Department of Agriculture and the US Department of Energy it was found that biodiesel is one of the most efficient fuels, with an energy balance(ratio of output energy to fossil fuel input energy)of 3.215, while petro-diesel had an energy balance of only .8337. http://www.nrel.gov/docs/legosti/fy98/24772.pdf
Not only is biodiesel efficient, it is also very clean to burn. Carbon released into the atmosphere by the burning of biodiesel is carbon that was already in the atmosphere, and was absorbed by whatever plant was used in the feedstock. Therefore the net carbon output of burning biodiesel is very small. Other harmful emissions such as particulates, hydrocarbons, and sulfur oxides are also reduced. However NOx output from the burning of biodiesel is slightly higher than petro-diesel.
One of the main problems with replacing fossil fuels with biodiesel from plant oil is the substantial amount of farmland needed to grow the feedstock to produce the biodiesel. Using this much land for biodiesel crops would displace much of the land now used for food crops. Researchers are now trying to find the crop which yeilds enough gallons of fuel per acre to relieve the countries dependence on foreign fossil fuels, while using as little farmland as possible. The best crop found to date is algae. Which according to a study done by the National Renewable Energy Laboratory would produce 7.5 billion gallons of biodiesel per 780 square miles. Meaning it would take 15,000 square miles of ponds to grow the needed algae( Approximately 1% of the land now used in the United States for farming and grazing).
Biodiesel can be used in any diesel engine(check with manufacturer and engine warranty before use of biodiesel). Slight modification to hoses in older cars might be needed due to biodiesel's corrosive properties to rubber. Biodiesel being used today is commonly mixed with petroleum diesel to obtain the desired properties of biodiesel, and the lower cost of petrodiesel. Common mixes are B2, B5, B20 and B100(B20 being 20% biodiesel, 80% diesel and B100 being 100% biodiesel). Properties desired from biodiesel include; improved lubricity resulting in less engine wear and noise, higher cetane rating resulting in better efficiency, and less harmful emission. However biodiesel fuel economy in miles per gallon is approximately 2% lower than petroleum diesel.
Biodiesel Production Using Waste Oil
More Alternative Fuels
- Ethanol
- Methanol
- Propane
- Compressed Air
- Hydrogen
- Natural Gas
To read more about Alternative Fuels: http://www.eere.energy.gov/afdc/altfuel/altfuels.html