Falling prices for renewable energy are central to getting action on climate change, a common (some would say repetitive) theme of this blog. We can beat climate change without them, but at a price most people are currently unwilling to pay. All renewables are coming down in price, but solar faster than most. That makes this chart, updated monthly, from solarbuzz, one of the most important indicators around.
This month the news is particularly exciting. A 5% fall in solar prices in Europe (and 2% in the US) should make the replacement of nuclear power stations a whole lot easier. Remember that is a 5% fall in one month. Naturally that won’t be repeated for a while, but given that falls of 10% a year will make solar panels cheaper than coal this decade (depending on location) that’s not a bad effort.
Of course the major issue to be solved is the question of storage/demand shifting to deal with the lack of sunlight at night and during the winter, but there is one other obstacle that needs to be jumped however, if small/medium scale solar is to become a major part of our energy systems. That’s the issue of inverters. Photovoltaic panels produce DC electricity at voltages too low for most purposes. To make this useful we need to convert it to AC, using an inverter.
In the early days of solar panels inverters were expensive, but panels were so much more so that this hardly mattered. (Since the early systems were generally not grid connected there were also the battery and regulator costs, which made inverters an even more minor part of the system.
As time has gone by inverter costs have fallen, but not nearly as fast as panels. Solarbuzz keeps track of them to, and this month inverter prices fell, but so little they didn’t register on their measures.Unless inverters start coming down faster they’ll become a major obstacle to cheap photoelectric power, at least for residential systems or projects like school/factory roofs. Is much research going into fixing the problem? I haven’t heard of any, although that certainly doesn’t mean it isn’t happening.
Australian firm Plasmatronics have made a major contribution to the spread of remote power systems by creating cheap, high quality charge controllers for batteries to prevent damage from overcharging or overdrawing. Inverters are a bigger market, since they are used both for remote and grid connected systems. However, like charge controllers, they are still a bit of a niche, easily ignored by research institutions. I hope someone’s on the case.