Skip to content

Pumping Up Storage

July 17, 2012

This is a play on pumped storage, where water is pumped uphill to a reservoir, and then released to flow downhill through a turbine to generate electricity.

It’s the only proven method for storing large amounts of electricity, though there are claims that batteries and compressed-air can also store electricity for use on the grid.

Pumped storage has been used for decades when it was economically viable.

It was first used by Connecticut Light and Power in 1927 to pump water, using electricity generated by the hydro-power plant, back to the lake which was the source of water for their hydro-power. This is as close to perpetual motion as is probably possible.

Today, the motivation for storing electricity is to find a method for using the electricity generated by wind turbines at night, when it isn’t needed. Wind farm operators have been known to sell their electricity, produced at night, at a loss of 1 cent/kWh so they could collect the 2.2 cents/kWh subsidy from the government. This turns an unneeded product into a money maker at taxpayers’ expense.

Wind is unreliable and expensive. Storage is intended to lower the cost of wind generated electricity by building expensive reservoirs and dams.

EnergyBiz magazine devoted an entire section to storage, using guest articles, in an effort to promote the concept. IntelligentUtility has produced a Webcast to promote storage experiments at Duke and Sothern California Edison.

These publications are staunch supporters of wind and solar, and of cutting CO2 emissions.

Building dams to create reservoirs isn’t cheap. The exception is where the hydro power generation is already in place, such as the example in Connecticut. There is also the problem of finding areas suitable for storing water at an elevation that permits the use of hydro turbines.

While theoretically possible, it isn’t usually economically viable, but it would allow wind turbines to generate electricity at night to pump water uphill so that it is available to generate electricity during periods of daytime peak demand.

Storage is also needed for solar power, since clouds can interrupt the generation of electricity on a minute-to-minute or day-to-day basis. This includes PV solar on roofs where batteries on the distribution system would act as “dynamic load controllers”, a euphemism for storage.

Since costs are incurred locally without sufficient local benefits, there is an attempt to “socialize” the cost across regions or the entire country.

The story goes, “since everyone benefits from reducing the carbon footprint, everyone should bear the cost.” And since the Federal Energy Regulatory Commissions (FERC) has done this for transmission lines, FERC can also do it for pumped storage.

Here again, there is an attempt to shift the cost to taxpayers who don’t benefit directly from the storage of electricity. Historically, it has been the person who benefits directly, who pays for the improvement.

Compressed air can be stored using electricity generated at night, and then used to drive air turbine generators during peak periods. The principle is the same as pumped storage, but it’s not necessary to build reservoirs and dams. There is the problem of finding underground caverns (such as used for storing natural gas) or constructing large enough containers for storing the compressed air.

As for batteries, there have been a few built the size of a house that can store limited amounts of electricity. Banks of batteries could also store electricity on a distribution system.

A few experimental battery installations have been installed.

The latest concept is to build “warehouses of storage” using batteries. Again, while theoretically possible, the cost is great. And something not mentioned by the proponents of “warehouses of electricity”, is that batteries last for relatively short periods of time and have to be replaced. This is an added cost that will be borne by taxpayers or ratepayers.

Wind and solar are expensive methods for generating electricity. All the storage proposals merely add to the cost. As shown in earlier articles, wind and solar can’t replace all our coal and natural gas power plants. In fact, renewables, excluding hydro, produce less than 3% of our electricity.

The reason given most often in support of these proposals is to reduce our carbon foot print. Once again, global warming distorts the energy sector with Don Quixote like proposals.

*  *  *  *  *  *

If you find these articles on energy issues interesting and informative, you can have them delivered directly to your mailbox by going to the Email Subscription heading below the photo.

 

*  *  *  *  *  *

© Power For USA, 2010 – 2012. Unauthorized use and/or duplication of this material without express and written permission from this blog’s author is strictly prohibited. Excerpts and links may be used, provided that full and clear credit is given to Power For USA with appropriate and specific direction to the original content.

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s