RHF wrote:
Solar* {Non-Burning} Electrical Power Plants
produce little Pollution and that is why Prez
Obama will get them up and running soon.
* but they destroy the natural environment
with massive arrays covering the landscape
Levelised cost
Since a solar power plant does not use any fuel, the cost consists
mostly of capital cost with minor operational and maintenance cost. If
the lifetime of the plant and the interest rate is known, then the cost
per kWh can be calculated. This is called the levelised energy cost.
The first step in the calculation is to determine the investment for the
production of 1 kWh in a year. Example, the fact sheet of the Andasol 1
project shows a total investment of 310 million euros for a production
of 179 GWh a year. Since 179 GWh is 179 million kWh, the investment per
kWh a year production is 310 / 179 = 1.73 euro. Another example is
Cloncurry solar power station in Australia. It is planned to produce 30
million kWh a year for an investment of 31 million Australian dollars.
So, if this is achieved in reality, the cost would be 1.03 Australian
dollar for the production of 1 kWh in a year. This would be
significantly cheaper than Andasol 1, which can partially be explained
by the higher radiation in Cloncurry over Spain. The investment per kwh
cost for one year should not be confused with the cost per kwh over the
complete lifetime of such a plant.
In most cases the capacity is specified for a power plant (for instance
Andasol 1 has a capacity of 50MW). This number is not suitable for
comparison, because the capacity factor can differ. If a solar power
plant has heat storage, then it can also produce output after sunset,
but that will not change the capacity factor, it simply displaces the
output. The average capacity factor for a solar power plant, which is a
function of tracking, shading and location, is about 20%, meaning that a
50MW capacity power plant will typically provide a yearly output of 50
MW × 24 hrs × 365 days × 20% = 87,600 MWh/year, or 87.6 GWh/yr.
Although the investment for one kWh year production is suitable for
comparing the price of different solar power plants, it doesn't give the
price per kWh yet. The way of financing has a great influence on the
final price. If the technology is proven, an interest rate of 7%[69]
should be possible. However, for a new technology investors want a much
higher rate to compensate for the higher risk. This has a significant
negative effect on the price per kWh. Independent of the way of
financing, there is always a linear relation between the investment per
kWh production in a year and the price for 1 kWh (before adding
operational and maintenance cost). In other words, if by enhancements of
the technology the investments drop by 20%, then the price per kWh also
drops by 20%.
If a way of financing is assumed where the money is borrowed and repaid
every year, in such way that the debt and interest decreases, then the
following formula can be used to calculate the division factor: (1 - (1
+ interest / 100) ^ -lifetime) / (interest / 100). For a lifetime of 25
years and an interest rate of 7%, the division factor is 11.65. For
example, the investment of Andasol 1 was 1.73 euro per kWh, divided by
11.65 results in a price of 0.15 euro per kWh. If one cent operation and
maintenance cost is added, then the levelized cost is 0.16 euro per kWh.
Other ways of financing, different way of debt repayment, different
lifetime expectation, different interest rate, may lead to a
significantly different number.
If the cost per kWh may follow the inflation, then the inflation rate
can be added to the interest rate. If an investor puts his money on the
bank for 7%, then he is not compensated for inflation. However, if the
cost per kWh is raised with inflation, then he is compensated and he can
add 2% (a normal inflation rate) to his return. The Andasol 1 plant has
a guaranteed feed-in tariff of 0.21 euro for 25 years. If this number is
fixed, after 25 years with 2% inflation, 0.21 euro will have a value
comparable with 0.13 euro now.
Finally, there is some gap between the first investment and the first
production of electricity. This increases the investment with the
interest over the period that the plant is not active yet. The modular
solar dish (but also solar photovoltaic and wind power) have the
advantage that electricity production starts after first construction.
Given the fact that solar thermal power is reliable, can deliver peak
load and does not cause pollution, a price of US$0.10 per kWh[70] starts
to become competitive. Although a price of US$0.06 has been claimed[71]
With some operational cost a simple target is 1 dollar (or lower)
investment for 1 kWh production in a year.
http://en.wikipedia.org/wiki/Solar_t...ure_collectors