Do the Math

  • With some simple arithmetic and the help of our Gasoline Energy Equivalents and Conversion Calculator, you can relate energy from different sources in varying amounts. A gallon of regular gasoline is a good benchmark to work from; it's familiar to everyone, yet its energy potential, compared to other sources like pounds of coal, therms of natural gas, or kilowatts of electricity, can be surprising.

    We also have a Therms & Barrels Calculator that lets you compare equivalents related to the energy in a barrel of oil.

    When thinking of energy use and potential waste and savings, keep in mind the concept of "pure" energy, no matter how it's expressed or what source it comes from. The important thing is how much energy is needed to do a specific amount of work. Energy consciousness means thinking about how efficiently you can apply the energy to the work, ranging from how you manage your water heater to how you approach and leave a stoplight in your car.

    No one can be entirely energy efficient, and we all have thresholds of patience, comfort, and enthusiasm. But energy consciousness itself, and the formation of at least some good personal energy habits, will make a big difference when we put all our habits together. Other good calculators:

    Soltrex Interactive Energy Calculator
    EIA Energy Kids Page Calculator
    U.S. Department of Energy Calculators

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renewable energy

Henry is really detailed in comparing VAWT versus HAWT. He is really helping all of us to weigh which one is better when it comes to wind power energy. Thanks Henry!

wind generator

Hi your wind project looks great and am very interested in your comments and stats you may already know this but I read somewhere that if you pour a mixture of carbon powder and fine iron fileings mixed with a quick setting resin like car body fillers and fill up the space in the middle of your coils this is supposed to greatly improve the efficiency of the generation.

Robert Webb

It is not true that HAWTs are inherently more efficient than VAWTs. There are good aerodynamic studies showing the efficiency is similar in theory. The issue is simply that to date vastly more has been spent on developing HAWTs.

In fact for small scale applications near the ground, where the wind is turbulent, we predict a 20% to 40% better output for a VAWT due to responsiveness to rapidly varying wind conditions.

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