EPRI to Evaluate Adding Solar Thermal Energy to Natural Gas and Coal Power Plants
10 November 2008
The Electric Power Research Institute (EPRI) will lead two projects to help electric power companies add solar energy to fossil-fueled electric power plants, reducing fuel costs and plant emissions. Dynegy Inc. and NV Energy will host case studies at their natural gas combined cycle facilities with project participants including Salt River Project, Southern Company and Progress Energy.
Both projects involve adding steam generated by a solar thermal field to a conventional fossil fuel-powered steam cycle, either to offset some of the coal or natural gas required to generate electric power or to boost overall plant power output.
The projects will be conducted in parallel, with one focused on natural gas plant technologies and the other on coal plant technologies. As part of the natural gas project, case studies will be conducted at Dynegy’s Griffith Energy Facility in Kingman, Ariz., and at NV Energy’s Chuck Lenzie Generating Station near Las Vegas.
These projects will demonstrate a near-term and cost-effective way to use large amounts of solar energy at commercial scale to provide clean electric power. These ‘hybrid power plants’ will combine the low-cost reliability of existing fossil power plants with the environmental benefit of renewables, and help companies meet federal and state mandates to reduce their emissions of air pollutants and greenhouse gases with renewable energy.
—Bryan Hannegan, vice president of Environment and Generation at EPRI
Currently, 27 states in the US have enacted RPS (Renewable Portfolio Standard) policies. Some include specific mandates that a percentage of the requirement be met with solar energy. However, most current solar applications are not cost-competitive with other power generating options. Using solar to augment coal or natural gas potentially is the lowest-cost option for adding solar power to the generation fleet, as it utilizes existing plant assets, EPRI says. And because the highest-intensity solar energy typically is within a few hours of peak summer loads, it makes solar augmented steam cycles a particularly attractive renewable energy option.
These projects will provide a conceptual design study and two detailed case studies. Design options to retrofit existing plants will be analyzed and new plant design options will be identified. EPRI will rely on its expertise in solar technologies, steam cycles, and plant operation, as well as past solar and fossil plant studies. EPRI holds two patents in solar steam cycle optimization.
The technique was first tested in Australia, and there could be some value to it.
It would be much more cost effective to require cogeneration in all new buildings.
But the governments are remorseless in imposing high electrical prices on the consumers by increasing the capital costs and operating costs of power plants.
Renewable means expensive. If you doubt it look up the price of solar cells and calculate the cost of electricity if the sun shone for 24 hours a day. Do the same for windmills if the wind blew all the time.
This does not include the price of the land required. How many people have enough land for solar cells or wind turbines to run their SUVs off of hydrogen. Renewable energy is a fraud by politicians on the public to get votes of uninformed people. ..HG..
Posted by: Henry Gibson | 10 November 2008 at 04:33 PM
@ Henry,
Henry, concentrated solar thermal is probably the least costly renewable energy source, and the most readily expandable for the Soutwest US. One of the past problems with solar thermal for utility scale production was you paid the capital cost for a big boiler that you could only use for half the day. This increased the capital cost of the power. By constructing a hybrid plant, which can keep the boilers busy 24x7, the capital cost component of solar thermal electricity should drop.
Hopefully your photovoltaic numbers will be obsolete soon as well, given that Nanosolar and Solyndra are both producing at volume now.
Posted by: Healthy Breeze | 10 November 2008 at 04:52 PM
Take one open cut coal mine, add a power station with buffer zone and top with one large cooling pond and you have a lot of land Henry.
You're also mixing topics. The post is about adding solar thermal to existing power stations not backyard power generation.
Posted by: critta | 10 November 2008 at 06:38 PM
The best? siting of relatively smaller output and renewable plant is either off grid or out at the extremitieas where advantage is gained from peaking and boosting in theory. In practice the siting of novel plant at the large generators would be educational; and inspirational.
Having a working plant for the engineers to observe, and the benefit from experiencsed and skilled labor and construction facilities may have longer term spinoffs. If held too close may serve to disprove the viability of such plant , but with the right appoach could enable and spawn and upskill a workforce.
Posted by: arnold | 10 November 2008 at 07:11 PM
Combining two or three types of power plants could effectively produce a higher EROEI and a more reliable power supply.
Hydro + wind turbines is also a very good pair when the huge water reservoirs are used to store surplus wind power (= a free battery) and supply energy for peak demands and low wind periods. Hydro Power Cos are very reluctant to change their ways.
Co-generation is another similar approach to enhance power plants efficiency.
Will the private sector use those efficiency enhancing possibilities to reduce GHG and cost without being mandated or being given tax credits etc.?
Posted by: HarveyD | 10 November 2008 at 07:12 PM
This is a good move, since mains supply power stations generally require a backup supply of energy. Pure solar plants require energy storage in the form of molten salt tanks to allow power generation to continue at night.
This hybridizing of existing plants looks like a good, cheap way to make existing infrastructure greener.
Posted by: Roger | 10 November 2008 at 07:14 PM
In the future, most of the natgas/coal fired plants will also have windfarms / solar-thermal plants in the vicinity.
When wind blows / sun shines, it will be used, on other times, natgas/coal will be used. So overall, there will be reduction in the use of fossil fuels.
Mr. Henry : Out of $600 billion that US spends on its military, atleast $100 billion goes to defend the Persian Gulf and this is the largest subsidy to Oil. Soon, that will CHANGE.
Posted by: Max Reid | 10 November 2008 at 08:08 PM
This site contains the plans which are used to produce thermal power by focusing on coal plant technology and natural gas plant technology.
Posted by: Eddisionklein | 10 November 2008 at 08:46 PM
I always thought it would be good to combine solar thermal, algae biodiesel, and IGCC/CCGT plants together. The solar thermal would provide peaking power, the IGCC/CCGT plant would provide baseload power, and the solar thermal would provide fresh water for and the IGCC/CCGT plant would provide CO2 for the algae biodiesel.
Posted by: Dan A | 10 November 2008 at 08:58 PM
I can see how you can vary the output of a natural gas station to match demand and wind/solar, but I understood that coal stations were mainly for base load, and hence cannot track demand or solar/wind.
Natural gas is an incredibly valuable resource - it should be used to balance demand / renewables so they can be matched up with coal, or better still nuclear.
Using natural gas as a base load supply is crazy.
The trick is to make it last as long as possible as a load equalization fuel.
Posted by: mahonj | 11 November 2008 at 01:44 AM
“Using natural gas as a base load supply is crazy.”
Welcome to the real world. Say hello to Putin while you are at it. I hear he is a nice guy. No reason to import coal from the US or the Aussies at a fraction of the cost.
Posted by: Kit P | 11 November 2008 at 06:43 AM
Wind and Solar power (without batteries) have to be combined with another major power generation source that can be varied quickly for reliability and high efficiency.
Unfortunately, most major power sources are not easily and quickly varied.
Hydro is one exception. Hydro (water use and electrical power output) can be varied as quickly as associated Wind and Sun power vary. In other words, Wind or Sun or Wind + Sun power could supply the base load while hydro would pitch in only on an (as required basis). Nothing is lost when hydro output is reduced because potential power is accumulated in the huge associated water reservoirs. Secondly, full or fuller water reservoirs maximize hydro plants power generation capabilities. In most places, it would be easy to add a few more water turbines to handle higher peak loads with the water saved with Wind + Sun generated power.
Unfortunately, Hydro people don't like to share the pie with Wind and/or Sun Power energy producers even where they would both benefit.
The Hudson Bay and Labrator shores are ideal areas for combined Hydro/Wind power generation plants. Many Hdro plants are built in high quality wind (8 and 9) areas. A few thousand 5 mega-watt wind turbines could double + the power generation in the area.
The arrival of a few million PHEVs and BEVs may increase the clean electrical power demand enough to implement the above. Ontario could progressively close its coal fired power plants and delay building more nuclear units.
Posted by: HarveyD | 11 November 2008 at 08:44 AM
@mahonj says: I can see how you can vary the output of a natural gas station to match demand and wind/solar, but I understood that coal stations were mainly for base load, and hence cannot track demand or solar/wind.
What they are talking about here is to augment a coal or gas plant. This can be as simple as preheating the steam before entering the main boiler. Less energy is required to create the superheated steam when the sun is shining. You could also just add a secondary stream of steam to the turbine. Either way the turbine will be able to handle a bigger electrical demand with the same amount of fossile fuel.
It applies to peak load because the sunniest times are the highest electric load (air conditioning). The sunniest times are also when your solar collectors are adding the most heat. You can end up with an old coal baseload plant with built-in peaking ability or a NG peaker plant that uses less gas.
Hard to believe we don't already do this stuff...
Only minor issue I could see is with mirrored concentrators near a coal plant. Someone will need to clean them regularly...
Posted by: PABlo | 14 November 2008 at 08:46 AM