Solar PV and Battery
Solar Electricity Generation
I have been watching the development of Solar photovoltaics (PV) for many years.
Initially as part of a design project for an all terrain expedition vehicle / motorhome. A roof predominantly covered with PV panels and a bank of 10 deep cycle batteries. I also went to a Caravan and Motorhome show and saw a PV panel mounted on a devise that looked like a satellite dish support, but instead of having a dish, it had a PV panel. It tracked the sun, to maximise power generation.
The Oyster SunMover System is an intelligent GPS controlled solar tracking system. It can automatically track the suns path throughout the day and adjust as necessary to maximise solar energy capture making it more efficient than standard fixed solar panels.
The system itself consists of a 75W solar panel attached to a specially designed electronic mechanism which is controlled internally via its own control system in the roof unit making installation simpler. On average the system is capable of harvesting approximately three times the power of a 75W fixed solar panel on its own. This is even more important in the winter months where the angle of insolation (the angle of the suns rays on the earth) is much greater i.e. the sun is effectively lower in the sky. The Oyster SunMover can adjust the elevation (the angle of the solar panel) to maximise energy harvest throughout the year.
This was a long time ago, and I can't remember if the make was Oyster or the price. However, at over £2000 before being discontinued, for just one panel, it was not directly pursued.
I did think about building a frame about 20 x 8 ft, which could elevate and swivel, so the roof could be covered with PV panels in drive mode, and then positioned for maximum benefit when parked. Turning it by hand every half an hour or so. Also. it could be two layers, so that in the right position, part could be an awning as well. Verdict, all to cumbersome. Human factors would indicate lack of use and leave it in the stowed position. Effectively flat to the roof, which is also safer as you don't have to worry about driving off with the rig up. Yes, I have seen the very unlikely event occur, with a tipper truck drove off with the back still up, struck a bridge and almost toppled over. Could have been even worse if it was power cables. Best avoided.
Solar at home - garden
The first solar at home was a small panel attached to a water feature. That worked well. Limited functionality, but did what was intended.
Followed by 4 PV panels in a frame from Maplin, about 200w in all. They were attached to a bank of deep, traction, 12v batteries. The batteries were attached in turn to a 1000w inverter, again from Maplin, and a 600w from Stirling. The Maplin inverter was more powerful that the Stirling, so it could run all the water features and garden water irrigation associated with my rainwater harvesting, but had a high standing drain. It also had a low voltage alarm, which unfortunately would go off during the night sometimes during the winter. So it could only really be used in the summer. The Stirling was a much better inverter, and at 600W could run the equipment, but the start up loads were something of a stretch. The Stirling was bought for use in a motorhome, and was only repurposed for the garden function, when the motorhome project came to an end.
To help generate more electricity, even in winter, another set of 4 PV panels were bought. A small tree in next door neighbour's garden had died and fallen down. That gave an un-obscured southern aspect form an outhouse roof. That worked well for a while, with good production for a relatively small array. Unfortunately, one stormy night, the tethers broke at the frame was blown into the neighbour's garden. It was not recoverable.
Back to one array, which is still going as I write this.
I watched the technology develop though many years.
Solar at home - mains connected
As I was watching the progress of PV, I would form time to time check out the return on investment and payback period for a full, mains connected PV system. The costs went down as did the government grants or incentives. The answer was always 25 years, or thereabouts, for the payback period.
Eventually, we started looking into PV with more of a hope for installation. Add that to the roof being refurbished. The decision was made.
A product for GB-Sol was considered. It would cover the whole roof, including the triangles made by the bay window roof.
PV Panels
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Inverter
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Batteries
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