Marketwatch looks at the Ivanpah solar project. They comment
The $2.2 billion Ivanpah solar power project in California’s Mojave Desert is supposed to be generating more than a million megawatt-hours of electricity each year. But 15 months after starting up, the plant is producing just 40% of that, according to data from the U.S. Energy Department.
I looked at the Ivanpah solar project last fall, when the investors applied for a $539million federal grant to help pay off a $1.5 billion federal loan. One of the largest investors was Google, who at the end of 2013 had Cash, Cash Equivalents & Marketable Securities of $58,717million, $10,000million than the year before.
Technologically the Ivanpah plant seems impressive. It is worth taking a look at the website.
That might have been the problem. The original projections were for 1065,000 MWh annually from a 392 MW nameplate implying a planned output of 31% of capacity. When I look at the costings on Which? for solar panels on the roof of a house, they assume just under 10% of capacity. Another site, Wind and Sun UK, say
1 kWp of well sited PV array in the UK will produce 700-800 kWh of electricity per year.
That is around 8-9.5% of capacity. Even considering the technological superiority of the project and the climatic differences, three times is a bit steep, although 12.5% (40% of 31%) is very low. From Marketwatch some of the difference is can be explained by
- Complex equipment constantly breaking down
- Optimization of complex new technologies
- Steam pipes leaking due to vibrations
- Generating the initial steam takes longer than expected
- It is cloudier than expected
However, even all of this cannot account for the output only being at 40% of expected. With the strong sun of the desert I would expect daily output to never exceed 40% of theoretical, as it is only daylight for 50% of the time, and just after sunrise and before sunset the sun is less strong than at midday. As well as the teething problems with complex technology, it appears that the engineers were over optimistic. A lack of due diligence in appraising the scheme – a factor common to many large scale Government backed initiatives – will have let the engineers have the finance for a fully scaled-up version of what should have been a small-scale project to prove the technology.