As an example, if a 1000 MW Solar Plant was built, what would its generation profile be on a typical day ( peak to trough)? How much land would it take? What would it cost? What is the construction time - permit to production?
$1 billion, Opening 2011, 280 MW, 3 sq. miles, 14 cents per KWH vs 10 cents for NatGas peakers and can produce power up to 6 hours after sunset.
This plant may NOT happen because an existing 30 percent investment credit expires this year, and a renewal was pulled from the energy bill the president signed in December. Congress will have to pass a stand-alone measure to keep the incentives.
I wonder why we have to find solar power plants in Spain?
Ronbo
Plant to brighten state's solar future
$1 billion facility to be among world's largest
Ryan Randazzo
The Arizona Republic
Feb. 21, 2008 12:00 AM
Arizona's solar-power supply is about to get a lot bigger.
A solar-energy plant planned near Gila Bend will be among the world's largest when it opens in 2011, Arizona Public Service Co. said Wednesday.
If the solar-thermal plant passes upcoming regulatory and tax hurdles, it will be built and operated by a Spanish company. APS will buy all the electricity from the plant to supply its 1.1 million customers.
As environmental concerns and rising costs affect traditional fuel sources, solar likely will be a bigger part of the mix of power supplies that feed the state's energy needs.
At 280 megawatts, enough to power at least 70,000 households, the plant will make even more energy than a similar facility announced in December.
Together, the two plants represent a departure from small research projects in favor of full-blown power generation.
"This is a turning point for APS and the future of the state of Arizona as we move to become the solar capital of the world," APS President Don Brandt said, estimating the Solana plant will cost more than $1 billion and cover 3 square miles.
"It will be the dawn of the Solar Age in Arizona," Brandt added.
Solar-thermal plants use mirrors to focus sunlight and heat up liquids. They make steam that spins turbines, just like coal or other power plants but without the pollution.
Officials say they plan to tap the state's abundant sunshine because it is becoming more likely that global climate-change fears will increase the costs of making electricity the old-fashioned way, with coal.
Solar-thermal plants work best in hot places, unlike the more common black solar panels that use a chemical reaction to turn light into electricity whether it is hot or cold.
APS, Salt River Project, Tucson Electric Power and other utilities announced in December that they will share the power from a 250-megawatt solar-thermal plant.
Unlike that partnership, APS will buy all the power from Solana, $4 billion worth over 30 years, making it a much bigger commitment from the utility.
"We will provide more solar capacity per customer than any utility in the United States," Brandt said.
Meeting peak demand
Abengoa Solar Inc., a Spanish technology company that has several smaller solar-thermal projects in Spain, North Africa and the United States, will build and run the Solana Generating Station.
Solana will use 2,700 "troughs" of mirrors lined up across former alfalfa farmland, focusing sunlight on tubes in the middle of the troughs.
The tubes will be filled with a petroleum-based chemical that will heat up to 735 degrees and transfer their heat to water, making steam and spinning turbines in two 140-megawatt generators. The petroleum liquid is reused in the tubes, not burned.
The plant also will use molten salt to store heat and continue generating electricity for as long as six hours after the sun sets. That's key in Arizona, where residents use the most electricity from 5 to 6 p.m., when the sun is low in the sky and common solar panels struggle to generate electricity.
To meet peak demand, utilities buy expensive energy from natural-gas plants.
"This will displace our most expensive form of generation," Brandt said.
However, solar plants cost more than coal, nuclear or even the most efficient natural-gas plants for the amount of electricity they generate.
APS will pay about 14 cents per kilowatt-hour, compared with about 10 cents per kilowatt-hour from natural-gas plants at peak demand.
The premium is worth it because coal and natural-gas prices are unpredictable, and emissions from those plants likely someday will be taxed for their contributions to global climate change, Brandt said. That makes predictable solar prices attractive.
New nuclear plants are being proposed around the country but will take years to get the proper permits and build.
The extra cost will be blended into existing APS rates, which are kept at about 9 cents per kilowatt-hour because of inexpensive energy from Palo Verde Nuclear Generating Station. Brandt said that, as the utility signs more solar contracts, he expects the price to keep falling.
Slow to develop
Solar power often is suggested in Arizona, but utilities haven't developed solar on a large scale because of the costs and intermittent power that doesn't match up with spikes in demand.
"To put it into our business model, until this point, it's been a challenge," Brandt said.
In 2006, state regulators tried to spur development by enacting a renewable-energy standard requiring that utilities get 15 percent of their electricity from renewable sources by 2025.
Brandt said APS would buy energy from Solana even without the mandate.
"Absolutely," he said. "This makes economic and operational sense."
Gov. Janet Napolitano said the plans for Solana show that utilities recognize the need for more renewable energy.
Napolitano has promoted alternative energy through her Climate Change Advisory Group and said that projects such as Solana bring economic opportunity.
Solana alone could create 1,500 construction jobs.
"You can create jobs, you can put Arizona at the forefront of new technology that can be sold around the world and you can help the environment at the same time," she said.
Abengoa breakthrough
Solana will be Abengoa's largest project in the United States and its first electricity plant here, although it already has several smaller power plants in Spain and several hot-water and industrial-cooling projects in the states.
Last year Abengoa opened a U.S. subsidiary to focus on building solar-thermal electricity plants in the Southwest.
Its current U.S. installations use mirrors to concentrate sunlight and heat water for prisons in Arizona, Colorado and California, a military base in Texas, and one scheduled to come online this year for a California Frito-Lay chip factory.
"I think this project is going to be an enormous change for the solar industry," said Santiago Seage, chief executive of Abengoa Solar in Spain. "This is one of the first cases where a utility relies on solar power for its day-to-day operations."
APS recently initiated a series of meetings to help the utility decide what type of power plants it should invest in to meet growing electricity demand. Peak customer demand at APS grows by about 280 megawatts a year, meaning Solana will meet one year's growth for the utility.
If the Arizona Corporation Commission approves the project, the next hurdle appears to be the U.S. incentive program. If a tax credit for solar-power plants is not renewed, Solana will not happen, Seage said.
An existing 30 percent investment credit expires this year, and a renewal was pulled from the energy bill the president signed in December.
Seage said that he is confident Congress will pass a stand-alone measure to keep the incentives. |
