1. The Ivanpah Solar Power Complex that BrightSource is building
near the California/Nevada border in the Mojave Desert will power
250,000 homes and reduce carbon dioxide (CO2) emissions by over
500,000 tons per year.
2. BrightSource's 400MW Ivanpah Solar Power Complex will produce
more electricity in one year than the total of all of the residential
solar installations currently installed in the US. [Note: Ivanpah is
the only utility-scale solar project currently under development in
the US that has reached this advanced permitting stage.]
3. If BrightSource Energy plants were built on less than 2% of the
land in the Mojave Desert, they would provide enough power for all of
the homes in California and reduce carbon dioxide (CO2) emissions by
over 30 million tons per year.
TEN FAQS ABOUT SOLAR THERMAL POWER
1. What is the difference between the terms "solar thermal power,"
"concentrating solar power," and "CSP"?
Solar thermal power is sometimes called concentrating solar power or
CSP. These labels refer to technologies that use the energy of the
sun to produce steam, directly or indirectly. The steam is then piped
to a convention power generation system to make electricity. The
difference between a solar thermal plant and a conventional
fossil-fueled power plant is that conventional plants create steam by
burning fuels that release carbon into the atmosphere.
2. What is the difference between solar thermal power plants and
photovoltaic (also known as PV) systems?
Solar thermal power plants, often also called Concentrating Solar
Power (CSP) plants, use sunlight to produce steam, which is then used
to generate electricity. By contrast, photovoltaic (also known as PV)
systems use special panels to collect sunlight and convert it directly
to electricity. "Thermal" refers to the fact that it is the heat of
the sunlight that is used, and "concentrating" refers to the fact that
solar thermal systems concentrate the sunlight, in much the same way
that a magnifying glass does, to harness its heat.
Solar thermal plants are large utility-scale projects that generate
enough power to serve tens of thousands of homes. Their power is
usually sold to public utilities, which then sell it to their
customers. Photovoltaic systems are usually much smaller and are
usually installed on residences, schools, or office buildings.
3. Where can solar thermal plants be built?
In theory, a solar thermal plant can be built anywhere that the sun
shines, however cost considerations dictate that they be built in
areas of high solar radiation – a measure of how much power can be
generated in a single square meter of surface area in a typical year.
The best solar radiation is found in high desert areas, such as the
Mojave Desert in Southern California, where the sun shines reliably
330 to 350 days a year. Another major consideration is that solar
plants need to be built in the vicinity of power transmission lines
serving markets large enough to use all of the power generated by the
plant.
4. How much land do solar thermal plants require?
The answer depends on two factors: a) the solar insularity (see FAQ
3) of the plant location, and b) the specific technology being used.
In general, a typical 100 MW solar thermal plant will occupy 600 to
800 acres. Installing solar power plants on an area covering only 1%
of the Mojave Desert would provide enough solar power to serve 75% of
the homes in California.
5. How much are atmospheric carbon emissions reduced by solar thermal
power plants?
Carbon emissions are reduced by 600 pounds for each MW hour of solar
power that displaces an equal amount of fossil-fuel power. Installing
solar power plants on an area covering 1% of the Mojave Desert would
reduce annual carbon emissions by over 20 million tons.
6. Is solar thermal power reliable and available when needed most -
during peak demand hours?
The peak demand period for electricity is the hottest part of the day,
when air conditioners are running in offices and homes. This is the
same time of day when solar power is produced. In addition, because
sunshine is reliable and consistent in the desert areas where solar
power plants are typically built solar power is also consistent and
reliable. Conversely, another common form of renewable power
production, wind power, normally has its peak production period during
the nighttime hours, and is much less predictable and reliable.
7. Are there ways to use solar power to provide electricity power both
day and night?
Unlike the photovoltaic systems typically installed on rooftops, CSP
plants produce their electricity by first producing steam then using
that steam to generate electricity. Thus, CSP plants can be fitted
with gas-fired boilers to produce steam when the sun is not shining,
enabling the plants to produce electricity at any time. This provides
valuable back-up generation capacity to utility companies for use when
wind power is not available, or demand is unusually high. Another
method is to install thermal storage to store heat during the daylight
hours and release that heat during the night to make electricity. At
this time, such storage systems are not economical, but it is
anticipated that the cost will come down and make the use of solar
power viable around-the-clock.
8. Will the cost of electricity produced by CSP plants vary in the future?
The cost of fuel represents about 60% of the cost of producing
electricity from fossil-fueled plants. CSP plants require no fuel,
thus the cost of the power they produce is not affected by the
vagaries and risks associated with fossil fuel prices. Other than very
slight increases in maintenance and operating expenses due to
inflation, the cost of power produced by a CSP plant will not change
over its economic life.
9. How does the cost of electricity produced by CSP plants compare to
the cost of electricity produced by fossil fuel plants?
Solar thermal power is probably cheaper than power from fossil fuels
when all cost externalities are considered. While many of the costs
of fossil fuels are well known, others (pollution related health
problems, environmental degradation, the impact on national security
from relying on foreign energy sources) are indirect and difficult to
calculate. These are traditionally external to the pricing system, and
are thus often referred to as externalities. In order to better
control this matter, legislative and regulatory bodies are moving to
require the sequestration of carbon to keep it out of the atmosphere,
or apply a corrective pricing mechanism, such as a carbon tax, to
fossil-fueled power plants. Either measure will lead to the cost of
solar thermal power becoming cheaper to the consumer than fossil fuel
based energy.
Even without pricing cost externalities, the cost of solar thermal
power is going down. As more plants are built and technologies
improve, this price should continuously drop over the next ten years
with the result that the price of solar power seems likely to be in
the same range as power from fossil fueled plants, even without carbon
emissions costs considered.
10. How does today's regulatory environment impact the development of
solar energy plants?
The combination of environmental concerns and persistently higher
prices for commodity fuels has caused a number of states to adopt
Renewable Portfolio Standards (RPS) that require their utilities to
purchase as much as 33% of their power from renewable energy sources
such as wind, hydro and solar by specified dates. These and other
regulatory mandates including federal mandates and tax incentives
provide an environment conducive to the development of alternative
energy solutions and make the building of solar power plants cost
effective.
A favorable governmental and regulatory climate makes the delivery of
renewable energies possible. And, these requirements, such as the RPS
in place for California that requires utilities to purchase 20% of its
power from renewable sources by 2011 and 33% by 2017, help to
encourage utilities to make the development of alternative energy
sources possible.
TEN FAQS ABOUT BRIGHTSOURCE ENERGY
1. What is BrightSource Energy Inc.?
BrightSource Energy, Inc. designs and builds large scale solar power
plants that can deliver low-cost solar energy in the form of steam and
or electricity to industrial and utility customers worldwide at prices
competitive with fossil fuels. BrightSource Energy enables industrial
and utility customers to lessen their dependency on fossil fuels by
providing a cost effective clean source of power during periods of
peak usage.
2. When and where was BrightSource Energy founded? By whom?
BrightSource Energy was founded as Luz II in 2004 by Arnold Goldman.
Mr. Goldman has been in the solar energy field for over twenty years
and was the founder and CEO of Luz International Ltd., which built
nine large solar power plants in the 1980s In 2004 Mr. Goldman
reassembled a number of members of the original Luz International
executive and technical team and founded Luz II to develop a new solar
energy technology to take advantage of renewed interest in the use of
renewable energy to produce electricity and regulatory / legislative
support of such projects.
In 2006, the name of the company was changed from Luz II, Inc. to
BrightSource Energy, Inc. The Luz II name was retained by
BrightSource's wholly owned subsidiary in Israel, which is responsible
for engineering and development, and the supply of solar fields for
BrightSource plants.
3. Where does BrightSource Energy's financing come from?
BrightSource Energy is a privately held company. Its principal
investors include: VantagePoint Venture Partners, Morgan Stanley,
Draper Fisher Jurvetson, J.P. Morgan, And Chevron Technology Ventures.
4. What was Luz International? What are SEGS?
Luz International was the solar technology company that successfully
designed, built, financed, and operated nine solar energy plants in
Southern California between 1984 and 1991. Luz International remains
to this day, as the only company in the world to have built
large-scale commercial solar thermal projects – the 350 MW SEGS
projects in the Mojave Desert – which are still in operation today.
SEGS is the acronym for Solar Electricity Generating Stations, which
was the name given to the type of power plants built by Luz
International in the Mojave Desert in Southern California between 1984
and 1991. Fifteen of the key members of the Luz International
engineering and commercial team that built those SEGS are now key
members of the BrightSource team.
5. How does a BrightSource Energy power plant work?
Unlike solar photovoltaic technologies, which convert sunlight
directly to electricity through silicon or other solid-state
materials, BrightSource Energy's solar thermal technology converts
sunlight to heat, in the form of steam or hot air that is then used to
drive a turbine to produce electricity. The technology used by
BrightSource is called Distributed Power Tower, or DPT.
6. How does DPT work?
DPT™ stands for Distributed Power Tower and is a BrightSource design
based on the solar power tower concept proven by the DOE Solar I and
Solar II projects in the 1980s. The innovations that BrightSource has
brought to the power tower design make it far less expensive to build
and more efficient in its production of electricity.
A DPT solar field, known as a Solar Power Cluster (SPC), consists of
an array of thousands of relatively small flat glass mirrors placed in
the desert and an associated power tower and receiver (solar boiler)
which converts the light received into useful heat. These mirrors
reflect sunlight onto the collection surface of the solar boiler
approximately 300 feet in the air on top of a tower. The concentrated
sunlight focused on the collection surface is used to directly heat
steam, which then drives a turbine/generator to produce electricity.
7. How does the BrightSource solar thermal solution compare to other
renewable energy resources and to other solar energy solutions?
A properly located and constructed solar power plant is a more
desirable source of power generation for utilities than other types of
renewable energy, such as wind plants, because solar plants produce
the greatest amount of power at the time when the demand on the
utility is greatest – sunny afternoons. A BrightSource DPT plant has
a further advantage in that it can be fitted with auxiliary boilers,
which will enable them to reliably supply electricity to the grid
during both solar and non-solar hours, and during any extended period
of solar disruption.
8. Does this solution mean that photovoltaic systems make no sense?
Both photovoltaic systems and solar thermal systems have a role to
play. Photovoltaic installations are well suited for individual
installations in residences and small commercial or industrial
facilities where they complement and supplement energy supplied by
public utilities. By contrast, solar thermal installations are
designed to provide large quantities of power for direct sale to
public utilities to reduce the need for electricity produced by fossil
fuel power plants.
9. How does the cost of energy from a BrightSource Energy solar
thermal plant compare to the cost of electricity provided by a PV
system?
Solar thermal power, using BrightSource's DPT solar technology can be
produced for about half the cost of electricity produced by
photovoltaic systems, making solar thermal the lowest-cost form of
solar power yet available. The economy of scale and lack of costly
specialized materials will allow BrightSource plants to achieve the
lowest cost of solar electricity in the world.
10. How does BrightSource Energy's approach differ from other solar
thermal solutions? Is it better? Is it more efficient?
BrightSource's DPT technology has several significant advantages over
other solar thermal technologies: a) unlike most solar thermal
technologies, DPT plants produce steam directly from solar energy, b)
the steam has a much higher temperature (550° C vs 380° C), which
results in more efficient operation, c) the mirrors that reflect the
sunlight move in two dimensions to follow the sun during the day and
during the seasons (other technologies only move in one dimension), d)
the glass used in the mirrors is less expensive because it is flat,
not curved, and e) DPT solar fields can be installed on uneven or
sloping ground.
11. How does DPT technology differ from the technology used in the
original SEGS plants?
The solar fields for the SEGS plants built by Luz International
utilize long rows of curved glass mirrors to heat synthetic oil, which
is piped to a heat exchanger to produce steam at about 375° C. This
steam is used to drive a steam turbine to produce electricity. By
contrast, the DPT 550 technology uses thousands of small flat glass
mirrors (known as heliostats) to focus sunlight on a solar boiler
located on top of a tower. The sunlight heats steam directly to a
temperature of about 550° C and the steam is used to drive a steam
turbine to produce electricity.
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