21 November 2010

Moving to a new site

I've decided to move my posting to a new site, with a very descriptive url: kurtmuehmel.com.

For the time being, this site will remain active. In the future, however, I plan to import the archives of this site into kurtmuehmel.com. At that point, this site will be closed.

Thanks for reading!

11 November 2009

So an economist writes something about geoengineering...

...and he gets it totally right!

Sound like a bad joke? Thankfully it's not.

After the flare-up around Steven Levitt and Stephen Dubner's misadventure into the world of geoengineering advocacy in their new book SuperFreakonomics (The New Yorker's takedown is the most colorful, ClimateProgress' multiple posts are the most thorough), it's good to see Mike Konczal*, author of Rortybomb, getting things very right.

Here's the opening paragraph from his recent post, "A little more on Geoengineering":

Having spent a fair amount of brainpower and energy over the past month trying to convince right-leaning folks and libertarians that having three bureaucrats sit down and come up with a default 'vanilla option' checking account won't be a first step on the road to serfdom, I'm somewhat confused by the wave of excitement among right-leaning folks and libertarians for having three bureaucrats sit down and come up with the optimal level of sulfur to be pumped into the stratosphere at the north and south poles. (emphasis added)

Now, I know that no one is every perfectly intellectually consistent, but the idea of a select group of, dare I say it, elites undertaking a climate experiment that will have implications for individuals worldwide seems to mesh more closely with the techno-totalitarian model of thought more than the "Don't tread on me" ethos that these folks normally espouse. (That's the long way of saying, "I agree!")

The post continues with a smart evaluation of some of the game theory inherent to the geoengineering calculus (mainly, what are the results of a government credibly signaling that it will undertake geoengineering?) as well as the obvious issues of fairness (what happens if a project helps 6 billion but harms 1 billion?). Good stuff, and worth reading in its entirety.

Konczal closes his post with a very cogent summary of why geoengineering is a very bad idea:

But the biggest problem, you may have notice, is that we aren't removing any carbon from the air in this strategy. Thought exercise: the carbon could be at a point where global temperatures would rise 5 degrees, but we've engineered the stratosphere to be 5 degrees cooler by putting sulfur in the stratosphere. So we are net neutral temperature. Things that are related to carbon in the atmosphere that aren't temperature related, like ocean acidification, would continue to go crazy.

But now let's then assume that the sulfur is causing too many side effects, and we want to shut it down. Then what happens? The sulfur rains out over the course of a short time period, say a year, and then the Earth heats up 5 degrees very, very quickly. No gradual increase over this time period; we have the same carbon amount as we had before. We haven't lost any weight, we were just wearing bigger pants. That would be a nightmare situation, and as such even if the side-effects were terrible it would be difficult to "turn off" such a plan.

We can't all be experts in each others fields; most climate scientists will never fully grasp the finer points of econometrics and most economists will never fully grasp the finer points of radiative forcing, but Konczal, in the vein of Paul Krugman, does a great job of showing that there is nothing inherent to being economics-minded that requires climate-blindness.

My suggestion: read Rortybomb, you'll likely gain some depth in a subject that may not be your specialty.

*To be perfectly precise, Mike is a financial engineer, not an economist.

15 September 2009

Legislating Energy Information

One particularly appropriate role for government to play in otherwise free markets is requiring that all of the economic actors (producers, consumers, merchants, etc...) have access to the information necessary to make good (dare I say "rational"?) decisions. Knowing that it is often difficult for consumers to obtain and interpret certain types of relevant information, requiring producers to present such information in a clear and consistent way will typically lead to more efficient results overall.

American consumers are most familiar with this sort of obligatory labeling in the form of the ubiquitous "Nutrition Facts" labels, present on all food products since 1994. Without this information, it would be prohibitively difficult for the consumer to evaluate the nutritional value of two different foods and make an informed choice. Imagine trying to compare the caloric or sodium content of two different types of cookies. How would you do that in less than 10 seconds in the supermarket aisle? Yet for the producer, it's relatively simple and low-cost calculation compared to other parts of the production chain.

Energy Efficiency Labeling in Europe
In the case of energy efficiency, it is the European Union which stands ahead in requiring that clear and consistently presented information be available to consumers. Thanks to the EU Energy Label program, from washing machines to automobiles, the efficiency of consumer products is clearly presented on a color-coded scale running from A to G. At a glance, consumers can evaluate the efficiency and better estimate the total cost of ownership of these products. The intended result is, of course, lower overall energy consumption as consumers, whether motivated by cost or by environmental concerns, choose higher efficiency products.

Energy Efficiency Labeling in the US
Clearly borrowing from this design, the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) has proposed a similar label for buildings, called the Energy Quotient.

This is a positive step, but there is a danger in the proliferation of different labeling standards. Standardization (as in the case of the EU Energy Label or the US Nutrition Facts) is vital to ensuring the usefulness of the information. Should a consumer prefer anEnergyStar rated appliance, or an appliance with a B-rating on the EU Energy Label? Should a homeowner look for a LEED-certified building, or a B-rated Energy Quotient building?

This is where government action becomes key. Both the EU Energy Label and the US Nutrition Facts programs are the result of government decree. The fact that they are now ubiquitous, standardized, and, as a result, useful comes from this legislative origin. Voluntary, industry-led labels, while laudable, are insufficient in this regard. The EU has already done it's part, the US needs to now follow suit.

Next Steps
Going beyond the predicted energy efficiency of a product, real-time information on a consumer's energy consumption is the holy grail of energy information. In his excellent (and free!) book, Sustainable Energy - without the hot air, David MacKay compares the current process of paying for energy consumption (monthly bills, often based on estimations) to going grocery shopping in a market with no price tags, filling up your cart, and then paying by weight on your way out, based on the average cost of all the goods in the store. Giving consumers real-time information on how much energy they are using and, most importantly, how much that is costing them, is one of the biggest steps that we can make in reducing energy consumption at the individual level.

The role, then, for government, is to require that this information be made available for the interested consumer. New building codes may require that houses be wired to collect and present this information, new communication standards will have to be established to ensure that the various devices can communicate with one another, and utilities will be required to broadcast real-time energy prices. If this can be done without a government decree, all the better, but I certainly have my doubts.

Steps are being made in this direction, one good example being software like Google's Power Meter. At the level of the consumer, the advent of the smart grid will most likely be realized through the availability of this information. The most important future advances in energy will come not from incremental gains in the efficiency of obscure thermodynamic cycles, but rather the integration of information technology with energy technology.

21 August 2009

Energy Storage: Remember the Resolution!

Energy storage capacity is important, really important, to ensuring the success of intermittent energy sources like wind and solar. This point is often overlooked when we see graphs like the following:

 

That's solar irradiance over 23 hours in a few different sites. Obviously there is the diurnal variation, but it otherwise looks relatively smooth and predictable. Note that the resolution of the graph seems to be roughly two hours (i.e. each data point  is the average of the solar irradiance during the hour before and after it.) Consider, however, a similar graph but at a 10-second resolution:

  

Here we begin to see that storage may be even more important than we previously thought. Not only is it a question of maintaining power throughout a regular and predictable diurnal cycle, but also stabilizing power output in response to massive and unpredictable intra-minute variations (you try predicting exactly when a cloud will pass over a site). The same goes for wind power:

 

The average (the thick, blue line in the middle) is quite steady, but the daily lines are all over the place in this appropriately-named "spaghetti graph". Remember: the presentation of data can have profound effects on its interpretation, be sure you know what you're looking at.

The above two graphs are coming from MegaWatt Storage Farms (somebody, call a web developer, stat!), an energy storage developer brought to my attention via Greentech. They're a young company but entering a market which can be expected to grow quite rapidly in the future (they predict that California alone will require 4 GW of storage by 2020 to meet its renewable energy goals); keep an eye out for similar companies that look to develop energy storage capacity, without marrying themselves to any one technology.

12 August 2009

Keeping Coal in Context

Imagine a software solution that can increase the efficiency of a coal-fired power plant by 1%, i.e. power output is increased by 1% while the same quantity of coal is burned. This improvement costs $100,000 to implement, per power plant.*

We know that, as of 2006, there was 1,216 GW of coal-fired power generating capacity installed worldwide. For the ease of numbers, let's assume that the average plant capacity is 500 MW and that none of them yet have this technology, yet all would accept it. That gives a total of 2,432 plants awaiting this improvement. Is it a good investment?

The total investment would be $243 million. The result, however, would be 12 GW of carbon-free (relative to the business-as-usual scenario), baseload-quality generating capacity. That is about six times the current installed photovoltaic generating capacity, at an installed cost of about $0.02/watt.

Compare that to solar photovoltaics which dream about getting down to the $1/watt of installed capacity. This seemingly minuscule improvement to coal technology is 50 times cheaper than the solar PV dream scenario.

Coal rightfully has a bad reputation, but there are two ways to think about this:

  1. Improving the efficiency of the installed stock can result in massive carbon savings. Just because you may not like coal doesn't mean that it's not an extremely important area of investment for climate change mitigation. Just imagine a system that increases efficiency by 2%!
  2. Even if we increased installed solar PV capacity by 600%, it would only have the impact of increasing the efficiency of coal-fired power plants by 1%. We need to deploy solar PV and other renewable energy technologies much more quickly and much more broadly.

Take your pick for which interpretation you prefer, but we must understand that addressing climate change will require a mind-boggling massive effort. We simply cannot afford to ignore any useful technology in finding a solution. Let's get to it.

* Reference was made to a technology with these price and performance characteristics by an investor on a panel organized by the Yale Center for Business and the Environment. 

07 August 2009

Bad News for Better Place

After reading this headline the other day: "President Obama Announces $2.4 Billion in Grants to Accelerate the Manufacturing and Deployment of the Next Generation of U.S. Batteries and Electric Vehicles" my first thought was, "This is bad news for Better Place."

Although I've swooned over Better Place and its founder Shai Agassi, I see this big, glaring hole in their strategy:

As soon as battery technology improves, something which a lot of people are working on (see above), the model is toast!

Imagine this scenario (one which I think makes people wary of all-electric cars):
Spur of the moment, you decide to drive from Chicago to San Francisco. You jump in your gas-powered car and hit the road. You drive for 3 hours at an average of 60 mph (180 miles). You stop for some gas and food (45 minutes all together). Back in the car for 4 hours at an average of 60 mpg (240 miles) and then you crash for the night, 420 miles from home. Rinse and repeat until you're staring at the Pacific.

Current battery technology would not let you do that. You wouldn't make the first, 180-mile leg, let alone the second, 240-mile leg. The Better Place model, if properly implemented, would make it possible. But so would better battery technology!

Imagine the following scenario instead:
You have the same revelation, but this time you jump in your all-electric car with its Obama-funded, super-duper battery pack which is good for 300 miles. The first leg drains it to 40%. Since it's a magic, future battery, the 45 minutes of charging get's it back up to 90%. On that 90% charge, you're good for 270 miles, just enough to get you to your destination for the night, where it gets a deep charge, bringing it back up to 100% for the following morning. A few days later, you're in San Francisco, never having entered a Better Place swap station.

Of course, getting a battery pack that is good for 300 miles is no easy feat and it's not at all certain that even $2.4 billion will get us there. But building a new battery swapping infrastructure and coordinating the various standards and finances between the manufacturers, station owners, consumers, etc... is no easy feat either!

To put it bluntly, every incremental advance in battery technology is another nail in the coffin of Better Place. A revolutionary advance in battery technology is their death knell.

Shai, I think you're great, but I'm very skeptical.

06 August 2009

Concentrating Solar Power (CSP) is Flexible

OK, maybe not that flexible, but I'm nevertheless a big fan of concentrating solar power (CSP), a technology rightfully known as "solar base-load", where the heat of the sun is concentrated via mirrors and the resulting high temperatures are used to generate steam to run a turbine.

That's one reason why I was happy to read at EcoGeek that eSolar, a company I've written about in the past, has recently turned on their 5 MW Sierra SunTower facility for the first time. For the hard facts, I'd suggest either Fast Company's summary the quick facts sheet directly from eSolar.

For my part, though, I'd like to talk about one reason why CSP is such a promising technology.

The French journal Systèmes Solaires laid it out nicely in their most recent edition. It's all about the flexibility of the design. Take this example:

Imagine that you're building a CSP facility and you have a fixed amount of land on which to place your solar collectors (in the case of a parabolic trough design) or mirrors* (in the case of a solar tower design, like that of eSolar). Depending on how you want to use the facility, you can vary the size of the heat storage and the turbine to have different uses such as:

  • Small Storage + Medium Turbine = Semi-base load (generating constantly between 8am and 7pm)
  • Medium Storage + Medium Turbine = Shifted semi-base load (generating constantly between 12pm and 11pm)
  • Big Storage + Small Turbine = Continuous base load (generating 24/7)
  • Big Storage + Big Turbine = Peak supply (when needed, likely during mid-day during hot months)

Further flexibility comes from the possibility of adding a gas-fired turbine in applications where you need an availability factor of nearly 100%. Given the changing demands on power sectors around the world, this flexibility is important indeed.

*I know, more accurately "heliostats", not simply "mirrors".

20 July 2009

Energy Efficiency Progress in China

While reading an article about energy efficiency in large buildings in China ( subs. req'd), I came across a surprising statistic: between 1978 and 2007, China has reduced the energy intensity of it's economy by a factor of 18.

That is to say, that it now takes 18 times less energy to produce the same amount of GDP as was the case 30 years ago. Another way to look at it is this: between that same period (1978-2007) growth in primary energy (that's a measure of all the energy used in the country) has been an annual rate of 4.66% while GDP has grown over the same period at a rate of 15.69%. As a result, energy intensity has fallen by 9.53% per year.

Here are the numbers, if you're curious:

Primary energy (TWh)

GDP (£billion)

Energy Ratio (kWh/£)

1978

5,110

36

140.2

2000

10,500

992

10.6

2007

19,168

2,495

7.7

Change (%)

4.66

15.69

-9.53

Jiang, P., Keith Tovey, N., Opportunities for low carbon sustainability in large commercial buildings in China. Energy Policy (2009), doi:10.1016/j.enpol.2009.06.059

Now, one shouldn't extrapolate too far from the case of China, it's unique in so many ways, not the least of which is that 15.69% annual growth in GDP. What should be retained, however, is the following:

  1. Energy efficiency and economic growth often go hand in hand.
  2. China, while still a "dirty" economy (its energy intensity is still five times that of the UK), it has come a long way in the last 30 years.