SUN, THE RESOURCE

Concentrating Solar Thermal Power: Clean Energy for the United States
Rob Bradley, July 20, 2009 (World Resources Institute)
and
Southpointe firm plans first solar power plant in Western Pennsylvania
Joe Napsha, July 21, 2009 (Pittsburgh Tribune-Review)
and
RWE, consortium to build solar plant in Spain
Vera Eckert, July 10, 2009 (Reuters)
and
75 MW Solar Power Plant Proposed In Washington State
10 July 2009 (Solar Industry)

SUMMARY
Concentrating Solar Thermal Power: Clean Energy for the United States, from the World Resources Institute (WRI), chronicles the abundance of the sun’s potential and the readiness of solar power plant (SPP) technology to supply utility-scale emissions-free electricity.

There are 500+ megawatts of solar power plant capacity now in service, primarily in the U.S. and Spain, but the potential of the resource and the technology have barely been tapped.

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WRI wants the U.S. Congress to move on policies that will allow the potential of SSP to fulfill itself and help transition the U.S. to a New Energy economy. Policy actions advocated by WRI are:

(1) Enact a law putting a price on carbon.
(2) Fund research, development and demonstration (RD&D).
(3) Create a national Renewable Energy Standard (RES).
(4) Push for international solar power plant technology partnerships.
(5) Upgrade the carrying capacity and intelligence of the transmission system.
(6) Reconsider New Energy investment incentives.

Putting a price on greenhouse gas emissions (GhGs, or “carbon”) moves the price of energy sources that spew them closer to their true cost and allows New Energy sources like SPP technologies to have higher relative value. WRI suggests a cap&trade system as an effective mechanism to price GhGs.

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As reported in STUDY PICKS WIND, GEOTHERMAL, the fossil fuels and other Old Energies have a tremendous head start in RD&D. The only way for SPPs to get a foothold in the energy arena soon enough to make an impact in the fight against global climate change is with stronger funding.

High up on every New Energy industry’s wish list is a national RES requiring regulated utilities to obtain a specific portion of their power from New Energy sources by a specific year. This guarantees a market for the New Energy industries’ products. Many state RESs have “solar carve-outs” requiring a specific portion of the required portion of New Energy to come from solar energy. Such a provision in a national RES would be especially good for SPP developers because utilities have already demonstrated an inclination to invest in SPP as a means to meeting RES requirements. SPP technology has a unique appeal attributable to its capacity to satisfy bigger chunks of the requirement with fewer projects.

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International technology partnerships would open SPP development in China, India, and emerging economies in the Middle East, North Africa and Latin America. Many such places are rich in solar resources and have rapidly growing energy appetites. A transfer of SPP technology is an especially intriguing idea in comparison to the more popular idea of partnering with emerging economies in the fruitless pursuit of the eternally elusive “clean” coal.

The EU already has underway a major public-private partnership for SPP development in the Middle East and North Africa (see DESERT SUN TURNS EUROPE ON), the World Bank Technology Fund has an SPP development program and China is developing its own SPP projects (see THE CHINESE CONQUEST OF NEW ENERGY CONTINUES).

In the many regions of the world where there is incipient SPP development (the U.S. Southwest, the Gobi, the Mahgreb), the limiting factor is the same: Transmission. Wires need to reach the remote areas where the SPPs are being built and operational systems need to have the high voltage carrying capacity and smart grid manageability to respond to the potential and intermittencies of large volumes of solar power.

For solar energy, and especially utility-scale solar energy, federal incentives have never been better. Solar projects are eligible for tax credits for 30% of the value of the investment and the benefit will be available to all investors, including utilities, for the next 8 years.

But that incentive is subject to political and economic vagaries. Like many at the cutting edge of thinking about how best to use government support mechanisms to grow New Energy, WRI wants to see the option of a feed-in tariff (FiT) available. With an FiT, utilities are required to pay above-market rates for all energy sent into the grid over a 15-to-20 year period. In Europe, FiTs have been shown to have a powerful affect on growth. The prospect of an FiT available to consumers and developers is likely to drive major action by utilities in the SPP arena.

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COMMENTARY
Terminology here can be somewhat confusing. SPP technology is also called Concentrating Solar Thermal power (CST) because the biggest, most potent form uses reflective surfaces to "concentrate" the heat of the sun rather than using the sun’s light to activate electricity from the chemical surface of photovoltaic (PV) semiconductor material, as is done in rooftop solar systems.

This CST solar power plant technology captures the heat and uses it to boil water to drive a turbine that generates power and sends it into the transmission system the same way that a coal or nuclear or natural gas plant burns its fuel to boil water to drive a turbine. Except that the solar power plant emits no greenhouse gases.

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There is one other unique and special feature of CST SPPs. While photovoltaic materials capture light (photo) and turn it into electricity (voltaic), the power cannot be economically stored in large quantities. Because power plants use liquids to capture the sun’s heat, the hot liquids can be stored and used when there is cloud cover or darkness, making solar energy a potentially fulltime, baseload source of power.

The 50-megawatt facility planned by a major German utility and its partners for Southern Spain will be the third such installation in the area. Like Andasol 1 & 2 which preceded it, Andasol 3 will use parabolic trough mirrors to concentrate the sun’s heat and molten salts to hold the heat in storage for short-term generating capacity in the absence of the sun.

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Another form of solar power plant is sometimes described as a solar “park” or “farm” to distinguish it from CST technology. It is usually of lower capacity than CST SPPs and uses a big array of PV panels. The 3-megawatt facility planned by a wireless telecommunications company for Western Pennsylvania and the 75-megawatt facility planned by a private developer for Cle Elum, Washington, are such PV SPPs.

One part of the world that has an immense solar resource but has been little developed is the Middle East and North Africa in general and the Arabian Peninsula in particular. Europe does not intend to allow the lack of development to go on much longer if it can help it. (See DESERT SUN TURNS EUROPE ON)

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QUOTES
- Fritz Vahrenholt, CEO, RWE Innogy: "The parabolic trough technology sets new standards for solar power production...It is suitable to large-scale applications and thanks to giant thermal salt storages can keep producing after sunset an electricity which is both reliable and absorbable by the transmission grids."
- From the Schilling and Esmundo study on New Energy funding: “…incumbent firms should begin (if they have not done so already) to develop strategies for transition to renewable energy options lest they become victims of disruptive technological change…”

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- CNN, quoted in Delivering on Earth’s Solar Potential: “What if you could provide the world with an endless supply of virtually carbon-free electricity; ensure a constant source of drinkable water to the world’s most vulnerable areas; avert some of the world’s future humanitarian crises; and save billions of dollars in the process? Concentrating Solar Thermal Power (CSP) proponents say there is no ‘could’ about it - it’s more a case of ‘can’.”