The report found that CSP with a six-hour storage capacity can lower peak net loads when the sun isn’t shining, enough to add $35.80 per megawatt hour to the capacity and operational value of the utility, compared to photovoltaic (PV) solar power alone, and even higher extra value when compared to CSP without storage. The net load is the normal load minus variable renewables such as photovoltaic and wind.
The additional value comes because thermal storage allows CSP to displace more expensive gas-fired generation during peak loads, rather than displacing lower-priced coal; and because it can continue to flatten the peak load in the evenings when PV isn’t contributing to the mix because the sun has set.
The report, “Simulating the Value of Concentrating Solar Power with Thermal Energy Storage in a Production Cost Model,” by NREL’s Paul Denholm and Marissa Hummon, noted that the $35.80 per megawatt extra value would come in a scenario in which there is relatively high penetration of renewables into the utility’s mix, about 34 percent. If the penetration was lower, the extra value would be lessened.
The authors simulated grid operations in two balancing areas primarily in Colorado. NREL is also using the same methodology it developed for the Colorado scenario for the more complex California system controlled by the California Independent System Operator. A report on the value that CSP with thermal storage adds to the California system is expected early next year.
The Colorado study marks one of the first times that the operational and capacity value of CSP with thermal storage has been evaluated using a production cost model, a traditional utility planning tool.
The NREL authors employed Energy Exemplar’s PLEXOS simulation model that allowed them to isolate the relative value of thermal energy storage (TES) with and without storage.
CSP with TES, with an ability to store thermal energy in, say, molten salt, can use its heat-energy to drive turbines at power plants over much longer stretches of the day.
“We’ve known for a long time that CSP with storage adds significant value, however, we are now able to quantify this value in the language utilities understand,” said Mark Mehos, manager of NREL’s Concentrating Solar Power program.
Compared to other renewable options, at high penetration levels CSP with TES can be dispatched to displace natural gas rather than coal. This is important because electricity produced from natural gas fired generators is typically more costly than that produced from coal.
"With CSP with thermal storage, you aren’t diving as deep into the generation stack, displacing cheaper and cheaper fuel,” Denholm said. “You’re always displacing the highest-cost fuel.”
Also, CSP with TES can lower peak net loads in the evenings when electricity use can still be high, but PV isn’t available. So, it helps utilities offset the need to build new gas-fired generators in order to meet the electricity demand when the sun goes down.
“CSP with thermal storage can continually reduce that peak demand as the peak moves into the evening,” Hummon said. “It continually maintains a high operational value and high capacity value.”
NREL is the U.S. Department of Energy's primary national laboratory for renewable energy and energy efficiency research and development. NREL is operated for DOE by the Alliance for Sustainable Energy, LLC.
David Glickson | Source: EurekAlert!
Further information: www.nrel.gov
Further Reports about: Colorado river > Concentrating > CSP > natural gas > NREL > photovoltaic (PV) solar > power plant > Power Plant Technology > Solar Decathlon > Storage of Greenhouse Gas > TES > Thermal > thermal energy > thermal storage
More articles from Power and Electrical Engineering:
Not Just Blowing in the Wind: Compressing Air for Renewable Energy Storage
22.05.2013 | Pacific Northwest National Laboratory
Iowa State Engineers Design, Test Taller, High-Strength Concrete Towers for Wind Turbines
16.05.2013 | Iowa State University
A fried breakfast food popular in Spain provided the inspiration for the development of doughnut-shaped droplets that may provide scientists with a new approach for studying fundamental issues in physics, mathematics and materials.
The doughnut-shaped droplets, a shape known as toroidal, are formed from two dissimilar liquids using a simple rotating stage and an injection needle. About a millimeter in overall size, the droplets are produced individually, their shapes maintained by a surrounding springy material made of polymers.
Droplets in this toroidal shape made ...
Frauhofer FEP will present a novel roll-to-roll manufacturing process for high-barriers and functional films for flexible displays at the SID DisplayWeek 2013 in Vancouver – the International showcase for the Display Industry.
Displays that are flexible and paper thin at the same time?! What might still seem like science fiction will be a major topic at the SID Display Week 2013 that currently takes place in Vancouver in Canada.
High manufacturing cost and a short lifetime are still a major obstacle on ...
University of Würzburg physicists have succeeded in creating a new type of laser.
Its operation principle is completely different from conventional devices, which opens up the possibility of a significantly reduced energy input requirement. The researchers report their work in the current issue of Nature.
It also emits light the waves of which are in phase with one another: the polariton laser, developed ...
Innsbruck physicists led by Rainer Blatt and Peter Zoller experimentally gained a deep insight into the nature of quantum mechanical phase transitions.
They are the first scientists that simulated the competition between two rival dynamical processes at a novel type of transition between two quantum mechanical orders. They have published the results of their work in the journal Nature Physics.
“When water boils, its molecules are released as vapor. We call this ...
Researchers have shown that, by using global positioning systems (GPS) to measure ground deformation caused by a large underwater earthquake, they can provide accurate warning of the resulting tsunami in just a few minutes after the earthquake onset.
For the devastating Japan 2011 event, the team reveals that the analysis of the GPS data and issue of a detailed tsunami alert would have taken no more than three minutes. The results are published on 17 May in Natural Hazards and Earth System Sciences, an open access journal of ...
22.05.2013 | Life Sciences
22.05.2013 | Ecology, The Environment and Conservation
22.05.2013 | Earth Sciences
17.05.2013 | Event News
15.05.2013 | Event News
08.05.2013 | Event News