Factor e Farm Energy Cycle

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Factoreenergy.jpg


Introduction

We need to start by defining our terms. We use:

  • 1 calorie = 4.2 Joules
    • This is the amount of heat energy needed to raise the temperature of one gram of water by 1 degree Celsius
  • 1 Calorie = 4200 J
    • calorie with capital C is the heat energy needed to raise the temperature of one kilogram of water by 1 degree Celsius
  • calory = 4.2 Joules
    • This is used for food energy values.

Furthermore:

  • One kilowatt hour (1 kWhr) is 3,600,000 joules or 3.6 megajoules; look up Joule on wikipedia; this is also equivalent to 1 Whr = 3.6 kilojoules = 15 kilocalories = 15 kcal
  • Solar energy coming to the earth is about 1 kW per square meter
  • 1 acre is about 4000 square meters
  • Thus, 1 acre intercepts a power of 4 megawatts
  • Given a single day has 6 hours of direct sunlight on average over the year, we have a total of approximately 24 megawatt hours per day coming to each acre of Factor e Farm, or a total of about 9 GW hours per year
  • Multiply 1 Whr = 15 kcal by 9G (billion) to obtain this yearly amount of calories:
    • 15 kcal * 9 billion = 135 Teracalories = 32 TJ
  • Compare to 1 gallon of gasoline equivalent
    • Consider that 1 BTU = 1055 joules
    • Gasoline has an energy content of about 114000 BTU per gallon
    • -> gasoline has an energy content of 120 MJ/gallon
    • -> The sun showers us with the equivalent of 270,000 gallons of fuel per acre per year at Factor e Farm, Missouri, central USA!!!