4 ms·

Most windows are poorly placed to collect sunlight – ok, don't use it on most windows. Sloped isn't really important. Southern facing and shade free is. Vertic

by jws 14y ago

Most windows are poorly placed to collect sunlight – ok, don't use it on most windows. Sloped isn't really important. Southern facing and shade free is. Vertical, southern facing isn't bad for high latitude folks. For instance, I have my non-tracking panels at the optimum angle for this time of year at 45°N latitude for 2.8kWhr/m^2/day[1]. If they were vertical it would only drop to 2.5kWhr/m^2/day. Going the other way, a 2 axis tracker would get 3.1kWhr/m^2/day[2]. So that is about a ±10% range for mounting options. Vertical loses more like 40% in the summer. [1] November is my worst month. It is cloudier than December. [2] Trackers never work out at my scale, ~600 watts of panels on a pole mount. It's always cheaper to just add another panel. [3] Standalone footnote: It is an island. Grid power is not an option. This time of year it is just running telemetry, cameras, and keeping the batteries from freezing, but during the summer I get 6.1kWhr/m^2/day which gets me around 3kWhr/day (woo hoo! 25¢ of electricity!) and that takes care of four people. I choose a generator over a battery bank big enough to ride out more than one cloudy day. It gives me redundancy if the solar/inverter system fails.

Retric 14y ago
Static solar panels at 45°N latitude only work for really remote areas or with heavy subsidies which are much better spent in southern areas. (Even adjusting for transmission losses.) http://www.nrel.gov/gis/images/eere_pv/national_photovoltaic_2012-01.jpg http://www.nrel.gov/gis/images/eere_pv/national_photovoltaic... Now, as your in a remote area it's worth considering, but even if it's minimally expensive there are still far better mounting options than vertical which makes the discussion somewhat moot IMO. Also, full time tracing may not be useful, but you can use a manual bracket to change the angle once in spring / fall and get noticeably more power. EX: (http://www.crown-international.co.uk/products/season-adjustable-solar-panel-mounting-frame/ http://www.crown-international.co.uk/products/season-adjusta...) Honestly, it's a cool idea, but space is not the problem with photovoltaics it cost to deploy which is really the only important question. PS: As to 25c / day, that's assuming you could get on the grid as long as it's worth paying for it can be worth far more than that.

by jws 14y ago

Retric 14y ago

Static solar panels at 45°N latitude only work for really remote areas or with heavy subsidies which are much better spent in southern areas. (Even adjusting for transmission losses.) http://www.nrel.gov/gis/images/eere_pv/national_photovoltaic_2012-01.jpg http://www.nrel.gov/gis/images/eere_pv/national_photovoltaic... Now, as your in a remote area it's worth considering, but even if it's minimally expensive there are still far better mounting options than vertical which makes the discussion somewhat moot IMO. Also, full time tracing may not be useful, but you can use a manual bracket to change the angle once in spring / fall and get noticeably more power. EX: (http://www.crown-international.co.uk/products/season-adjustable-solar-panel-mounting-frame/ http://www.crown-international.co.uk/products/season-adjusta...) Honestly, it's a cool idea, but space is not the problem with photovoltaics it cost to deploy which is really the only important question. PS: As to 25c / day, that's assuming you could get on the grid as long as it's worth paying for it can be worth far more than that.