The domestic solar energy industry is a con.

Yes, domestic solar is a con perpetrated against the consumer and the taxpayer by its vendor industry, whcih only survives on subsidies and deluded idealism.

Every engineer knows that central, large scale generation of electricity is always going to be an order of magnitude more efficient, and have massively less carbon footprint.

Factor in the carbon footprint and energy costs of
- all the thousands of men in little vans selling, installing and repairing domestic solar installations.
- all those batteries full of awful refined chemical pollutants, which only last a decade or so before needing replacement
- the manufacture, distribution and maintenance of one control system per 10kW/hr instead of one control system per 10GW/hr.
- more-complex reversible meters and the administrative overheads of reverse billing
- the lack of finely tuned engineering and human supervisors to optimise output
- the location of many of these devices in areas where solar as a source of energy is absurd
- the fact that these are almost never cleaned after installation

And then to top it off, most domestic solar power owners want a grid to connect to so they can draw power when the sun lets them down. So we the community pay for the grid infrastructure so they can have a backup solution that they pay nothing for in sunny weather. Every hour that grid customers with solar don't consume through it means idle capacity, which creates more cost for the rest of you who do.

Domestic solar power is fine if you want a sop to middle class conscience or you are an armageddon-prepper. Otherwise forget it: like buying a Toyota Prius you are doing more harm than good. Solar power should be done by the gigawatt, with storage using water or other technologies than batteries, in the Sahara or Arizona or Australia. A dinky little power plant on your roof is like building your own iron refinery in your backyard.


Government view of solar water heating

"Solar water heating pumps are likely to have a shorter lifespan than a traditional hot water cylinder (10 to 40 years)...

Two recent reports on solar water heating, one commissioned by the Ministry of Business, Innovation and Employment and one from the Parliamentary Commissioner for the Environment, concluded that solar water heating systems were so expensive that almost half of them were unlikely to give any significant savings over their lifetimes...

There are obvious and much cheaper things you can do to reduce your hot water..."

Consumer New Zealand, Issue 534, April 2013

Middle-class sop indeed.