In recent years the rapid development of wind farms, but because of its poor reliability of power output and unpredictable, therefore, to ensure power supply stability and profits increased, electricity suppliers racing to develop energy storage technology.
Hawaii officials hope that by 2030, 70% of energy needs to provide the origin, while the state is facing the problem of wind power generation, mainly the power sector is not able to excess wind power generators output to close to the company, can not enter in the weak wind power. If the local Maui (Maui), total wind power capacity could reach the island, a quarter of the peak power, peak power and peak demand, but time is not the same, which brought to Hawaii to complete difficult goals.
“New York Times” said that the best option currently seems to use batteries. In New York and California, the power sector is to develop a power storage technology, even to “carry” the space, namely the use of such lower price to buy midnight hours of electricity sold at higher prices after a few hours . In the Midwest, public utilities shows another power storage technology, in a minute or less time may be repeated several times for the conversion charge and discharge, to help power against solar, wind generator and wave transmission failure. In Texas, power companies placed in different locations through a transmission line connection from the battery to stabilize voltage.
Many enterprises believe that the wind turbines industry, renewable energy goals can be achieved. Hawaiian Electric spokesman (Peter Rosegg) said that if the energy source is intermittent, “No battery will not achieve its objectives.” The company has agreed to from the island of Oahu (Oahu) north of the coast to buy a wind farm power. 30 MW installed capacity of power plants by the Xtreme Power Company to install a 15 MW battery.
Luo Saige said the power plants in Hawaii the best location of wind farms is one of its power supply volatility and lack stability. In addition, the power generation market is Honolulu on the island farthest from the company’s load center location, even from the company’s high-voltage transmission backbone.
Xtreme Power president Kaluosike (Carlos J. Coe) said, the computer will try to keep the battery in the day most of the time in the semi-charged state. If the wind suddenly increased or decreased, the battery current will be stable, so that power seems to gradually increase or decrease.
Hawaii’s success lies in its wind power generation facilities, the frequency adjustment function. AC system to run 60 cycles per second, while the battery can be carried out in 60 seconds from the charge to discharge or change in the opposite direction, so as to maintain frequency stability. Battery system can be used for profit, at the lower price store electricity, while the release of higher electricity prices. The battery can hold 10 MWh of electricity, equivalent to a 30-megawatt power plant produces 20-minute full-load power delivery, amazing storage capacity.
First Wind Company and Xtreme Power battery companies did not disclose the cost of the system, but public figures, the cost of the wind farm is about 130 million U.S. dollars, the battery system, which costs 10 million U.S. dollars, the U.S. Department of Energy provided 117 million U.S. dollars of loan guarantees. (1 U.S. dollar equals 6.78 yuan)
Power storage cost and value for consumers is difficult to predict. Off-peak electricity during the storage cost, and the highest cost of electricity is very expensive. “New York Times” said that if renewable energy sources to reduce dependence on coal and natural gas demand, which is an additional benefit.
Kaluosike estimate the efficiency of the battery system for more than 90%. If this figure is confirmed, the battery system is indeed a major step forward. Currently, the most efficient use of energy stored in the form of pumped storage power station comes as its efficiency of 70% to 85%.
Electricity sector also used to store electricity and other strategies for FM. Beacon Power is building a component from the 200 flywheel power storage libraries, storage grid electricity, and ensure accurate AC system in 60 cycles. The top of the flywheel is a generator or motor may be alternately used as a device that can store or access in the flywheel energy. U.S. Department of Energy cost of 69 million U.S. dollars for small wind turbines this project provided 43 million U.S. dollars of loan guarantees.
U.S. Department of Energy as the use of compressed air energy storage project to provide support. Surplus electricity to pump air into underground caves, when you need electricity, empty of air into the gas turbine generators.
Tags: Wind power