NaS Battery Installation to be Largest in US

[allardjd 1,853]

This article is from Inside AEP, the house newsletter of the company I am retired from. It documents a fairly large demonstration of the storage of power in a way that can be returned the the alternating current grid.

The article is interesting, but disappointing in one respect. Though touted as a "2-megawatt battery", MW is a rate, not an amount. There's no clue in the article about the battery capacity in amp-hours or any other meaningful engineering data that would suggest just how much energy is actually stored or how long it can supply usable power. For example, the 12V battery in my car can provide 550 Amps to the starter, but not for very long. By that measure it is a 6,600 Watt battery, but at that rate it's capacity is exhausted in seconds. Therefore, don't be too impressed by the 2 MW figure provided in the article in the absence of "the rest of the story".

Note that batteries store energy that must be put in and taken out as DC current. Converting the AC in and DC out necessarily wastes some of the energy, but if you get it back when it's needed, in certain situations it's worth the cost.

It's progress and will help accumulate the knowledge needed to do this on a meaningfully large scale in the future. On a great enough scale (i.e. several orders of magnitude larger than this) this kind of installation could be used to levelize the power from some of the alternative sources, giving back power when the wind isn't blowing or the tide's not flowing or the sun is not shining. It's the hidden cost of having to do things like this that make up the economic and practicality millstone that hangs around the neck of many of the alternative power sources that are the darlings of the green people. You can't just do solar, you have to do something else too, to fill the gaps when the sun is shining on Australia.

[MartinW 0]

Very interesting John.

Incidentally, the biggest NaS battery systems are in Japan, Hitachi have one consisting of four 2MW NAS batteries.

As for wind power, only off grid systems require battery storage. Off grid systems require battery storage and an inverter to convert DC electricity to AC

Where there is a grid connection, it's the best environmental option, as there is no need for batteries or heat dumps. An inverter and controller converts DC electricity to AC and synchronises the waveform to a quality and standard suitable for the national grid.

Superconducting wing turbines are in development also. American Superconductors are working on a 10MW direct drive off-shore wind generator powered by high temperature superconducting wire.

Direct drive wind generator systems utilizing HTS wire instead of copper wire for the generator's rotor are expected to be much smaller, lighter and more efficient than conventional generators and gearboxes. The net effect is expected to be a lower cost of wind generated electricity, particularly for offshore wind farms. AMSC and TWMC also announced that they have received an award from the National Institute of Science and Technology's (NIST) Advanced Technology Program (ATP), which is providing $3.4 million in funding toward the $6.8 million research project to be conducted under the joint venture.

"The objective of the TWMC-AMSC research joint venture is to develop technologies that will enable the deployment of offshore 10 megawatt class, direct drive wind generators - double the power capacity of conventional systems," said AMSC founder and chief executive officer Greg Yurek. "The result will be more power delivered from each offshore wind turbine, which would significantly reduce the total costs of offshore wind farms

By replacing copper with HTS on the generator's rotor and utilizing a new high-efficiency stator design to be developed under this project, AMSC and TWMC estimate that they could produce 10 MW class direct drive generator systems that would weigh approximately 120 metric tons, or about one-third the weight of conventional direct drive generators with this power rating. Technically, weight reductions could be greater, albeit at a higher cost, giving wind energy system manufacturers and developers new options to design and deploy cost-effective offshore wind farms.

The 30-month cost-shared research project to be conducted by the joint venture with NIST funding calls for the development of new HTS wire and coil technologies that will help enable the design and manufacture of 10 MW class, direct drive AC synchronous generators for off-shore wind turbines. The targeted ultra-low-speed, high torque generators are expected to produce full power at 6 kilovolts at 11 revolutions per minute.

[hurricanemk1c 195]

Wow!

Thats big!

Kieran