Thursday, February 24, 2011

storing electricity

As readers know, I have moved out of Gangwon Province and so post here much less frequently.  In addition, I was in Canada for a month, having recently returned - to Korea, not Gangwon, which I miss very much.

Consequently, I missed the whole "Corrupt Governor" story and now am commenting on an article that only slightly relates to Gangwon Province.

National Geographic has an article about ways to store electricity for utilities.  We are not talking about AA batteries, but ways to handle demand surges for large regions.  Storing electricity is important if new alternative energy production methods are to become mainstream.  Solar and Wind power can provide great quantities of electricity, but not consistently.

The article discusses using flywheels and compressed air as energy storage but also mentions pumping water uphill during off-peak periods.

Beacon's flywheel facility can dispense power for up to 15 minutes, but if a power plant wants to store energy for a longer period of time, it can do so by pumping water uphill. When the energy is needed later, the water flows back downhill, powering turbines that generate energy.
This so-called "pumped-storage hydroelectricity" is one of the most common forms of electricity storage now being used on the grid. But the DOE is looking into cheaper systems that rely on compressed air instead of water.

One thing I find interesting here is how this is not really that new.  As a scout, thirty-something years ago, at the electricity generating dam in downtown bracebridge, I was told how, during low demand periods, they reduced the amount of water flowing through the turbines and building up the 'head'.  I have to admit that the dam in Bracebridge could not have stored much water this way as stakeholders upstream would complain, but I do like the idea. Instead of having the water flow down to produce energy used to pump water uphill to later flow down again, just leave it up there.

I guess the pumping to a purpose-built reservoir would solve the complaints and environmental problems.  it is also the route Yangyang Gun in Gangwon Province took five or ten years ago.  Also, here (an excerpt although the rest is behind a paywall):
ANGYANG, South Korea, Sept. 4 (Yonhap) -- South Korea has completed its biggest pumped-storage hydroelectric power station after 10 years of construction, a state-run electricity company said Monday. The power station in Yangyang, 215 kilometers northeast of Seoul, was constructed at a cost of 932.4 billion won (US$972.7 million) and is capable of generating a maximum of 1,000 megawatts ofelectricity an hour, according to the Korea Midland Power Co., one of the subsidiaries of state-owned Korea Electric Power Corp.A dedication ceremony for the facility, the country's fifth pumped-storage …
Not entirely on-topic, but still interesting is a discussion of how much power we will need in the future.

1 comment:

Kevin Kim said...

I'm all for gravity-operated energy, and would love to see more done with geothermal energy.

Interesting insights.