If the sun certainly attracts media attention, the wind is not, however, remains in California. The state has the third largest installed wind from behind Texas and Iowa in the United States. Indeed for many years California has pursued an aggressive policy with the aim of achieving a rate of 33% of electricity production from renewable sources by 2020. The wind should play a major role in this portfolio with the objective of 20% production alone.
In this context a number of projects funded largely by electricity producers are emerging. This applies to the Pacific Wind project: enXco, a subsidiary of EDF Energies Nouvelles and San Diego Gas & Electric (SDG & E) signed an agreement for the construction of a wind farm in Southern California with a capacity of 140 MW. enXco will own and construct the facility, while SDGE agrees to purchase the power generated for 20 years. The project is pending approval by the CPUC is expected to be operational by late 2011 – early 2012 and be maintained by enXco Service Corporation.
However, the grid 50 years old is not prepared to integrate intermittent generation-related fluctuations and wind-dispersed over the territory. Therefore an update of the infrastructure and deployment of new technologies is essential for the future.
Storing the key to the wind
To offset the intermittent nature of wind energy to offset the fluctuations, the producing electrics rely on storage systems. Last November Obama had announced funding of up to $ 620 million stimulus package, including $ 435 million will be awarded for demonstration projects of the intelligent network. The remaining funding is allocated to 16 projects for storage capacity experimental eventually to greater efficiency and better reliability.
In this regard Pacific Gas & Electricity (PG & E) has won one of 16 projects and got $ 25 million to initiate work on possible ways of storing energy from the wind during the night. PG & E plans to develop energy storage technology based on compressed air. The idea is to store the air and compress it into cellars where wind can produce a lot of energy and use this compressed air to spin turbines and produce electricity when the wind is fell. If the test proves successful the technology, 300 MW could be produced for an initial investment of $ 365 million. The project, however, must be approved by the CPUC which will raise the remaining funds needed.
A similar project was being developed at Sandia National Lab’s premises. The Iowa Stored Energy Park is expected to save $ 5 million per year with a capacity of 268 MW of storage compressed air. Indeed, the storage can meet the needs of growing consumption peaks that require adding extra power very expensive.
Similarly Beacon Power Corporation has installed a storage system using flywheels inertia connected to a wind farm in Tehachapi California. The system is part of the demonstration project flywheels inertia carried by the Californian Energy Commission. Tehachapi is an area with high potential. According to a report of the California ISO, up to 4200 MW of wind could be added in the coming years. The main function of these flywheels is to keep current on the network. However during periods of large fluctuations in consumption or production of transmission lines, they can be used to compensate for the lack or excess electricity to the grid.
New transmission lines needed
Another key deployment of wind energy is the transmission network. Large regions with significant wind resources are not those where consumption is most important. The three major areas are Altamont Pass (east of San Francisco), Tehachapi (southeast of Bakersfield) and San Gorgonio (east of Los Angeles). The problems are posed at the delivery of electricity across the territory. Producer Southern California Edison (SCE) said it had completed the first phase of Southern California Edison’s Tehachapi Transmission Project Renewable. The transmission network will be able eventually to carry a capacity of 4500 MW of electricity from renewable energy produced in the Tehachapi Valley and distributed to three million homes across Los Angeles County. The total project cost is $ 2 billion for a network of 173 miles (~ 280 km). The project represents only a portion of the $ 5.5 billion that SCE plans to invest in the transmission network in next 5 years. The project when completed will help ease the Los Angeles Basin.
The total cost for the addition of transmission to meet the objectives of 33% renewable energy production for 2020 was estimated at $ 15.7 billion. Also transport problems of renewables is not unique to California. A report recently published by the American Wind Energy Association has highlighted the need for a standard for renewable electricity and an updated infrastructure to connect about 300,000 MW of wind projects still pending connection to the grid.