Comments samircmi has made

bottling the wind

I liked the last paragraph too

A range of options is available for the remainder of the storage, including the use of plug-in hybrid cars, Mr. English said. The idea behind plug-in hybrids is that the owner of a car would charge the batteries every night when demand and cost of electricity were low. The next day, under a contract between the utility company and the driver, the car would be left plugged when not in use, and the power company could reverse the flow of electricity and draw power out of its batteries during times of peak demand.

The idea of moving our cars with wind-generated electricity sounds great to me.

Its puzzling to me though that they didn't mention compressed air energy storage (CAES), which as the ESA figure linked to above shows, is the lowest cost bulk storage technology. It can also ramp quickly, operate at high efficiency under part load, and appears to be widely available in wind-rich regions throughout the continental united states. The capital cost looks too high to make it readily economic, but it certainly looks better than sodium sulfur batteries in the short run. I guess blowing air underground is less sexy than high-tech batteries.

(Matt Wald's "Storing Sunshine" in the  July 16th NYT does mention CAES however)

Sean asked about additional motivations for storage beyond simple arbitrage. One big one is transmission constraints. Storage allows you to put much more wind capacity behind a given transmission line and also allows you to run the line from the wind farm at a higher capacity factor thus better utilizing the transmission capital. If we start building dedicated transmission lines to remote wind resources, storage may become increasingly important.

Another reason to consider storage is that at high penetrations wind gets a smaller capacity credit. The declining load carrying capacity means that you need something else on line to come on when there is a lull. In the limit of high wind penetrations the value of wind is just the variable cost of running an open cycle gas turbine or something similar which can ramp quickly. So storage (together with other strategies like coupling geographically separated and temporally uncorrelated wind farms) can help firm up wind at high penetrations.

It also means that you use less fossil fired capacity to back wind. Remember that wind capacity factors are like 25-35%, so even if you have your wind capacity matched to your peak load, a large chunk of your energy is still coming from some other source. If that source is hydro (as in Denmark, with neighboring Norway providing lots of balancing) then no problem. If you are balancing with natural gas or even worse an old intermediate load coal plant, then you are really not doing a great job cutting CO2 emissions.

So if you have lots of transmission capacity to spare and can tie wind farms across the country, or if you have lots of eco-friendly hydro (not a lot of that in the great plains though), then you might not need storage. Otherwise, storage might be a good thing to consider. And considering lots of transmission projects are facing huge NIMBY (not in my backyard) and BANANA (build absolutley nothing anywhere near anything) issues, storage could likely play a big role as wind continues to expandOn American Electric Power to install large battery banks to store wind energy posted 2 years, 2 months ago 10 Responses

agreed!

Efficiency? YES! Renewables? YES!

I agree, I agree, I agree. Lets do all of it!

But if CCS gives a way to make climate change mitigation easier, then lets take look at it. The carbon price needed to bring in CCS for power generation (~$30/tCO2) is equivalent to about 25¢/gal of gasoline. Is that really that much? And even if it is, thats not a reason to ignore it as a potential solution given the urgency of the problem. Any technology that has the potential to get us off of "business as usual" in a significant way and quickly is worth pursuing.

I'm just going throw this out again because its worth repeating - when I saw if the first time it really conveyed the urgency of this issue to me:

Base on current trends (BAU), the emissions from coal plants in the 2003-2030 time period will be comparable to all the carbon emitted from coal plants over the past 250 years

(Socolow, R., 2005: Can we bury global warming?, Scientific American, pp. 49-55, July)

big picture

This is not just about US tax subsidies because its not about just the US. This expansion in coal capacity is already well underway in China, and I honestly don't see a way to influence what is happening in emerging economies other than by to lead by example. China has extensive gasification experience and a deep concern for air quality issues. If pilot plants in OECD countries can reduce the "first-mover" risk with CCS, there is a good chance it could be deployed quickly on a large scale.  We can say we hate coal, but its a cheap commodity with a stable price that is readily available in many regions of the world. Its going to be used one way or another (at least in the short term). We can't wave the renewables flag and ignore the fact that coal still makes good business sense. What has already started in China is beginning here. Despite the backlash against many proposed coal plants, many are still moving forward at breakneck speeds and many more are being planned. If we miss this boat the emissions from coal plants through 2030 will be comparable to all the coal emissions over the past 250 years [1]. OECD countries need to take a leadership role now.

1 Socolow, R., 2005: Can we bury global warming?, Scientific American, pp. 49-55, July
On Carbon sequestration is a costly alternative to renewables, not a transition to them posted 2 years, 2 months ago 21 Responses

Carbon Neutral with Biomass Co-gasification

Co-processing coal and biomass could reduce carbon emissions from synthetic fuels. The use of coal gives you the scale economies needed for these types of plants as well as the ability to use existing technology (co-gasification with biomass is already being done) and the biomass input with carbon capture and storage gives you negative emissions which brings the overall emission rate down to near-neutral thus making this approach viable in a carbon-constrained world.

With CCS, the GHG emission rate for coal F-T liquids could be reduced to about the rate for crude oil-derived fuels. The net GHG emission rate could be reduced further, to near zero, via coprocessing biomass and coal with CCS so as to exploit the negative emissions of storing photosynthetic CO2. At a carbon price of $100/tC the co-processing option is the most economically attractive of all the options considered for F-T liquids production and requires far less net biomass input to realize near zero GHG emissions than conventional biofuels such as cellulosic ethanol.
If the CO2 captured in F-T or IGCC plants were used for CO2-EOR, the economics of CO2 capture and storage would often be attractive even at a carbon price of $0/tC. CO2-EOR  pportunities in the USA (and perhaps elsewhere) are sufficiently large to make the CO2-EOR application an attractive way to gain extensive near-term experience with gasification-based energy and CCS technologies and the opportunity to "buy down" the costs of these technologies substantially as a result of learning by doing.

http://www.princeton.edu/~ssuccar/Williams_Pres_NETL_2007 ...

http://www.princeton.edu/~ssuccar/Williams_GHGT8_2006.pdf ...
On Coal-to-liquid is a dead end if there's a price on CO2 posted 2 years, 2 months ago 3 Responses