Solar Energy can be used for heating, electricity produced by solar cell ,photocatalysis.
Continuing with the last answer,
Solar energy can be used in several architecture activities, such as water heating, to illuminate naturally the buildings, water treatment and cooking.
Also can be used to optimize the productivity in agriculture (green houses).
Héctor
Have a look to the DIERET cource: http://www.inforse.org/europe/dieret/ It includes section about solar energy, too
I would suggest first searching the internet on the topic, it is too wide for this forum.
Dear Sjoerd Nienhuys
Your suggestion will be helpful if you give some useful links
Solar energy at the top of the atmosphere arrives at a rate of 1,368 Watts/m2. The Earth is a sphere with a radius of 6,366,197 meters. Thus has a projected area normal to the Sun's light of 1.274e+14 square meters intercepting light energy at a rate of 1.742e+17 Watts.
Humanity uses 30 billion barrels of oil per year, 5.5 billion tons of coal per year, and 2.2 billion tons of methane gas per year. A barrel of oil contains 6.1 billion joules of energy. A ton of coal contains on average 23 billion joules of energy. A ton of methane contains 55.6 billion joules of energy. Oil is 85% carbon and a barrel of oil produces 486.9 kg of CO2. Coal is 95% carbon and a ton of coal produces 3,483.3 kg of CO2. Methane is 75% carbon and a ton of methane produces 2,750 kg of CO2. A barrel of crude oil costs $105. A ton of coal costs $55. A ton of methane costs $600.
So, this means that crude oil provides 183e+18 Joules per year or 5.80 trillion watts. It costs us $3,150 billions per year and produces 14.6 billion tonnes of CO2. Coal provides us 126.5e+18 Joules per year or 4.01 trillion watts. Coal costs us $302.50 billions per year and produces 19.2 billion tonnes of CO2. Methane produces 122.32e+18 Joules per year or 3.88 trillion watts. Methane costs $1,320.00 billions and releases 6.1 billion tonnes of CO2.
Since fossil fuels produce only 83% of our energy needs this means that humanity consumes energy at a rate of 16.5 trillion watts. Since fossil fuels cost only 78% of what we spend on energy each year, this means that humanity pays $6,118.59 billions of the $70,000 billion generated each year for energy. Fossil fuels release a total of 39.8 billion tonnes of CO2 each year.
Now dividing 16.5 trillion watts by 1.742e+17 watts obtains 1/10,565 this means the Sun delivers energy to Earth at a rate over 10,000 greater than humanity uses it. Applying a discount rate of 4.5% to a 20 year life cycle for equipment and applying that to the $6,118.59 billions humanity spends on energy each year obtains a fixed cost of $79,590.23 as the most we can pay for solar infrastructure and not increase the price of energy for humanity. This is a total installed cost of $4.83 for each base load watt. With a 20% capital utilization this price must be reduced to $0.97 per peak watt for solar energy to be competitive.
In 2003 I developed a hydrogen producing solar panel that cost $0.06 per peak watt. In December 2004 when Saudi Arabia went off its $22 per barrel price cap, I proposed to the Bush Administration that he buy crude oil from me at $25 per barrel made from US coal using solar hydrogen. I could make crude oil for $8.57 per barrel, and hydrogen for $4.00 per barrel equivalent.
http://www.scribd.com/doc/24911642/Report-to-OSTP-EOP-Dec-2004
In 2013 I proposed using these panels in China to make China an exporter of energy.
https://vimeo.com/52213948
Now each ton of hydrogen gas when burned produces water and releases 141.8 billion joules of energy. So, to replace the 520.27 billion billion joules of conventional energy with solar derived hydrogen requires 3.67 billion tons of hydrogen gas made from 33.03 trillion liters of rain water run off from 194,485 square kilometers of solar panels. At $10 per square meter total cost this has a capital cost of less than $2 trillion. A substantial savings over existing technology.
Humanity uses 280 million tons of plastics each year. This is growing at 4% per year. Plastics are made from acetylene which may be made from methane. Methane may be produced from CO2 in the air. Hydrogen is made from sunlight and rain water run off as I mentioned above.
2 CO2 + 2 H2O --> 2 CH2 + 3 O2
88 36 28 96
880 360 380 960
So, an additional 360 billion liters of water converted to 40 million tons of hydrogen is sufficient to capture 880 million tons of CO2 from the air to produce 280 million tons of acetylene, the feedstock for all plastics. This requires an additional 2,119 sq km of solar panels. An additional 21,190 sq km provides 2.8 billion tons of plastics per year at a very low price - adding it to the cost of fuel. Providing a feedstock from atmospheric CO2 - reducing CO2 levels by 8.8 billion tons per year. Also providing several hundred kg of plastics for fabrics, construction materials, machinery, vehicles etc.
http://www.youtube.com/watch?v=DoCCO3GKqWY
http://www.youtube.com/watch?v=lVMAeSNZZz0
The atmosphere is 400 ppm CO2. However, pre-industrial levels were 285 ppm. At the rate of production proposed above, CO2 levels would fall by 1.15 ppm and achieve preindustrial levels in 100 years. With a 4% growth this level is achieved in 48 years.
I had installed a 1kw solar power plant on my house ,It is very use full.The attachment contain the picture of four solar panels and its other equipments.
Here's a drawing of how it goes together. A few sheets of PET plastic, a water filled lens, and a photovoltaic target designed to break water down into hydrogen and oxygen using a high temperature photovoltaic process.
The advantage here is that most of the area is very low cost 150 um thick PET plastic film hot-press molded to shape. Silicon wafers are about $1,550 per square meter and 23% efficient. That's $6.74 per peak watt. Multi-junction wafers, based on Germanium, Indium Phosphide and Gallium Arsenide, are 65% efficient and cost $7,750 per square meter. That's $11.93 per peak watt.
The same multi-junction wafer driving a MEMS based electrolysis unit operating at 1,600x solar intensity costs $23,250 per square meter and is 55% efficient overall, costs $0.0265 per peak watt!
per 200 mm diam wafer
Type Cost Efficiency $/Wp
Silicon $49 23% efficient $6.74/Wp
Ge/GaAs/InPh $244 65% efficient $11.92/Wp
Ge/GaAs/InPh - MEMS $730 55% efficient (1600x) $0.0265/Wp)
Crystalline PET plastic masses 1.455 grams/cc and costs $1 per kg. Three sheets forming a lens cavity array that is filled with water to create high volume lens arrays consists of 150 microns each sheet, 450 microns for all three sheets. A square meter of lenses mass 655 grams and costs $0.65 per square meter. This adds $0.0012/Wp to the cost.
Wafer Cost: $14.58/m2
Lens Cost: $ 0.65/m2
$0.0277/Wp
In a location that collects 4.6 kWh/m2/day this system produces 23.46 kg/year of hydrogen from 211.14 liters of rain water run-off. An area that also receives 1,400 mm of water per year also collects 1,400 liters of rain water per year per square meter. So, 1,168.86 liters of purified water are produced along with the hydrogen.
The cost of capital over 30 years at 4.5% interest is $0.93 per year. Dividing this by the 23.46 kg/year of hydrogen obtains a cost of $0.0397 per kg of hydrogen.
Combining hydrogen with atmospheric CO2 obtains CH4.
CO2 + 4 H2 --> CH4 + 2 H2O
44 8 16 36
5.5 1.0 2.0 4.5
So, each square meter has the capacity to produce enough hydrogen to absorb 129.03 kg of CO2 and produce 46.92 kg of methane. At $0.70 per kg for methane and $0.003 per liter of water, and $0.015 per kg of CO2 absorbed we have a revenue per square meter of;
CO2 129.03 $0.015 $ 1.92545/year
H2O 1,274.43 $0.003 $ 3.82329/year
CH4 46.92 $0.700 $32.84400/year
The CO2 capture and conversion system has a capital cost of approximately $0.35 per kg per year of capacity. This equipment costs $45.16 per square meter of solar panel. This adds $2.77 per year to the operating cost bringing the total cost to $3.70 per year fo panel plus conversion equipment.
A hectare of panels will cost $152,300 in production whilst a CO2 capture and conversion system to make use of that hectare of panels will cost $451,600. Financed over 30 years at 4.5% interest will require payments of $37,074.35 per year. This same hectare will produce $386,018.40 per year in revenue, assuming no price increases for fuel, water or CO2 taxes.
Here's an 8 ft concentrator I built back in 1996 to test entire wafers.
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