Re:US solar plant costs fall another 30 per cent in one year
by Pxtl on Tuesday September 19, 2017 @11:50PM
(#15290672)
Retrofits may be expensive, but think about what low costs mean for new builds, especially multi-unit dwellings - well, not highrises that lack enough rooftop space, but lowrises and townhomes.
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Re:US solar plant costs fall another 30 per cent in one year
by dispo001 on Tuesday September 19, 2017 @11:53PM
(#15290691)
Beyond some height wind makes total sense.
Re:US solar plant costs fall another 30 per cent in one year
by adrianN on Wednesday September 20, 2017 @04:00AM
(#15291622)
You need pretty big rotors to generate enough electricity to pay for the embedded energy: http://www.lowtechmagazine.com/2008/09/urban-windmills.html
Re:US solar plant costs fall another 30 per cent in one year
by dispo001 on Wednesday September 20, 2017 @05:49PM
(#15298641)
Output scales with design, size, location and height. With "beyond some height" I mean really tall buildings would need just a tiny propeller. Micro turbines are nice for a very different reason. -- "Unfortunately, micro wind turbines deliver hardly enough energy to power a light bulb." The benefit from not siting in complete darkness starts at about 1 Watt, the example produces considerably more. -- "Payback time: 50 to 750 years" The interesting bit here is the static world assumption. No one can tell how manufacturing, wages/income, the economy, geopolitics, climate, migration, food, etc will change. There is lots of room for the grid to go down and it kinda already regularly does in the best of locations one time every 10 years. (atm the entire grid in Puerto Rico is down) -- While it would be nice to have a heater or a cooker small devices like led bulbs and radios are valuable when the power is out.