## HydroSolar Package calculations

Solar Constant and Energy Impacting on the Earth

Solar constant:
"The solar energy reaching the periphery of the earth's atmosphere is considered to be constant for all practical purposes, and is known as the solar constant. Because of the difficulty in achieving accurate measurements, the exact value of the solar constant is not known with certainty but is believed to be between 1,353 and 1,395 W/m2 (approximately 1.4 kW/m2, or 2.0 cal/cm2/min). The solar constant value is estimated on the basis of the solar radiation received on a unit area exposed perpendicularly to the rays of the sun at an average distance between the sun and the earth."
[http://almashriq.hiof.no/lebanon/600/610/614/solar-water/unesco/21-23.html]

The value of 6371 km used here is the Volumic Radius, ie the value giving a fairly exact value for the Earth's volume by the usual formula for a true sphere. Because the Earth is actually an oblate spheroid, other radii have been calculated.

Calculations:
Taking the solar constant to be 1.4 kW/m2, and the Earth's radius to be 6371 km, the cross-sectional area of the Earth is pi*r^2, ie 3.142*((6371*10^3)^2)=1.2753E14 sq m.

With the Earth at its average distance from the Sun, total energy received (ignoring atmosphere etc) is 1.2753E14 times 1.4 = 1.785E14 kW. This is equal to 178,500,000 GW (gigawatts). (For a world population of ca 6 billion, solar energy per person= ca 30,000 kW.)

1 year=365.25*24 hr =8766 hr. Total solar energy received/yr = 8766*1.785E14 kW-hrs = 1.564731 * 1018 KW-hrs = 5.6330316 * 1024 joules.

1 kilowatt hour = 3 600 000 joules = 3.6E6 joules. 1 kilowatt = 1.0 x 10-6 gigawatts

Power draw and Energy Usage
The following table (reproduced in the main article with one less-relevant column omitted) uses figures extracted from [http://www.worldpopulationbalance.org/pop/energy/index.php], converted using the factor "One tonne of oil equivalent equals approximately 12 megawatt-hours of electricity" from [http://www.bp.com/conversionfactors.jsp]. The 5th column is converted from the 4th column by applying the factor 1.37 (derived by dividing 12 megawatt-hours by 8766, the number of hours in a year).

The whole-world total at end is calculated from the China figure using the factor "China now consumes 13.6 per cent of the world's total energy." from [http://www.bp.com/genericarticle.do?categoryId=2012968&contentId=7006684].

 Country *Population **Energy §Consumption Power Draw Consumption per head per head, kW Australia 20155 119 5.9 8.083 Bangladesh 141822 17 0.12 0.1644 Brazil 186405 188 1.01 1.3837 Canada 32268 308 9.53 13.0561 China 1315840 1386 1.05 1.4385 Hong Kong 7041 24 3.38 4.6306 Egypt 74033 54 0.73 1.0001 France 60496 263 4.35 5.9595 Germany 82689 330 4.01 5.4937 Iceland 295 3 8.81 12.0697 India 1103370 376 0.34 0.4658 Indonesia 222781 110 0.49 0.6713 Iran 69515 156 2.24 3.0688 Italy 58093 184 3.16 4.3292 Japan 128085 515 4.02 5.5074 Kazakhstan 14875 53 2.56 3.5072 Kuwait 2687 23 8.37 11.4669 Mexico 107029 145 1.36 1.8632 Netherlands 16299 95 5.85 8.0145 Norway 4620 39 8.44 11.5628 USA 298213 2332 7.82 10.7134 Whole World 6000000 10000 1.67 2.2879
*(x 1000, 2004 estimate)
**(million tonnes oil equivalent)
§ (tonnes oil equivalent)

(End)

Last update 2006 Sep 18