Solar power and viable batteries – the next step forward for renewables?
Is solar power the next big hope to take forward renewables in Scotland and could viable batteries address the intermittent power issue?
Solar energy generation in Scotland has largely been confined to small scale domestic or community developments on rooftops of domestic houses, schools and other public buildings. It accounts for only 2% of renewable production. Now, eight commercial projects varying in size between 1.8MW and 19MW have been granted planning permission in Aberdeenshire, Angus, Perth & Kinross and Dumfries & Galloway.
Large scale solar projects are also being planned for the Borders and Fife, which enjoy greater sunlight radiation. Over 100MW of large-scale solar projects are in the planning stages or awaiting construction to add to the 153MW of existing solar capacity from more than 31,000 installations, mostly panels on peoples' homes. If all the planned projects are completed this could lead to a 66% increase in solar production in Scotland over the next couple of years. Still way below countries like Germany and Denmark, but progress.
This could be important for renewables because new onshore wind sites are becoming increasingly unpopular. Solar power attracts less opposition, not least because it is viewed as less of a blight on the landscape.
One important factor in the growth of solar has been the falling cost of photovoltaic panels. The price has fallen 80% over the last six years and likely to fall by a further 40% by 2017. This will make it competitive with fossil fuels.
Solar panels and onshore wind turbines can also coexist making even less landscape impact because they can be sited in the otherwise unused land between turbines. It also smoothes out the inevitable peaks and troughs of both forms of power resource as wind turbines typically produce most of their power in the winter and autumn while solar panels produce more electricity in the spring and summer.
While this is attractive it isn't an exact match and it still leaves a gap. The sun doesn’t shine at night and the wind doesn’t blow year-round.
Step forward the Tesla Energy system. Their new Powerwall system offering 10 kWh is targeted at domestic users. It is complemented by a commercial system termed the Powerpack offering 100 kWh storage, and a stack of 100 such units to form a 10 megawatt hour storage unit that can be used at the scale of small electricity grids. Whole communities could build micro-grid power supply systems around such a 10 MWh energy storage system, fed by renewable energy generation. A Chinese company is doing something similar, not as well, but they will probably catch up. The Chinese market alone is massive.
There is some scepticism about costs and scale, but there is little doubt that this is a big step forward in the use of, what is actually an old tried and tested, technology. Solar and viable batteries could be a big game changer for renewables.
We mentioned some scepticism about cost and scale of the Tesla battery system. Bloomberg are reporting on this in more detail, albeit it the context of US regulations. It may be that the storage solutions are still some way off. Not unusual for renewable technology!
- Posted in: Renewable energy