Sign up with GoogleMy house use about 600-1000kWh per month. This includes 2 geysers (one switched off for the most part), pool pump, stove, TV, computers, lights, gate motor etc.
I calculated, roughly, that if I want to go off the grid using solar panels and batteries, I need about R150 000 and I probably have to replace the batteries every 3-5 years.
I was wondering whether it may be feasible and more cost effective to use molten salt to store energy from the sun via solar mirrors, and then generate energy using a steam engine.
Some questions:
1) Size of the steam motor
2) How much salt is needed?
3) How many mirrors to heat up the salt?
4) Storage costs?
Initial estimates.
1) I think a 10-20kW steam engine may be sufficient. Maybe less?
2) According to this wiki article (https://en.wikipedia.org/wiki/Solar_thermal_energy), about 4000 cubic meters of molten salt can generate 100 megawatt for 4 hours. If my calculations are correct, I would need at least 800 liters of molten salt to generate 20kW for 4 hours. I have no idea how much the salt costs and which kind of salt would be the most cost effective option. Any input here will be greatly appreciated.
3) Any engineers that can help me calculate how many mirrors or maybe even Fresnel lenses are needed to heat up about 1000 liters of salt to 500 degrees Celsius to run the small steam engine.
4) How to store the molten salt? Will concrete be sufficient?
I have no idea about the prices for the above estimates. Any input that can help with these estimations will be great.
Thanks.
PS, I got thinking about this when I saw this video about fresnel lenses...
[video=youtube;XFw7U7V1Hok]https://www.youtube.com/watch?v=XFw7U7V1Hok[/video]
I calculated, roughly, that if I want to go off the grid using solar panels and batteries, I need about R150 000 and I probably have to replace the batteries every 3-5 years.
I was wondering whether it may be feasible and more cost effective to use molten salt to store energy from the sun via solar mirrors, and then generate energy using a steam engine.
Some questions:
1) Size of the steam motor
2) How much salt is needed?
3) How many mirrors to heat up the salt?
4) Storage costs?
Initial estimates.
1) I think a 10-20kW steam engine may be sufficient. Maybe less?
2) According to this wiki article (https://en.wikipedia.org/wiki/Solar_thermal_energy), about 4000 cubic meters of molten salt can generate 100 megawatt for 4 hours. If my calculations are correct, I would need at least 800 liters of molten salt to generate 20kW for 4 hours. I have no idea how much the salt costs and which kind of salt would be the most cost effective option. Any input here will be greatly appreciated.
3) Any engineers that can help me calculate how many mirrors or maybe even Fresnel lenses are needed to heat up about 1000 liters of salt to 500 degrees Celsius to run the small steam engine.
4) How to store the molten salt? Will concrete be sufficient?
I have no idea about the prices for the above estimates. Any input that can help with these estimations will be great.
Thanks.
PS, I got thinking about this when I saw this video about fresnel lenses...
[video=youtube;XFw7U7V1Hok]https://www.youtube.com/watch?v=XFw7U7V1Hok[/video]
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