My wife and I got a ride last evening in a Mitsubishi MiEV and were very impressed. It's a small but reasonably roomy 100 percent electric 4-person vehicle, range 50-60 miles, 22 hours to charge (from zero to full) on 110, 7 hours to charge on 220. Talking with its owner brought out an aspect to those numbers I hadn't considered, which is that if you drive it 20 miles, it can probably be fully charged again overnight because it won't be down to zero. Duh. Which means, in turn, that if your commute is not too long, you may be able to use it every day for several days ...
Anyway, that prompted a discussion, because my wife had seen a reference somewhere recently to how EVs (electric vehicles) may not be as clean as hybrids, depending on the fuels that the utility system in your region uses to generate electricity. I've also seen this issue raised a number of times, perhaps most prominently in a New York Times article discussing a Union of Concerned Scientists (UCS) study on the issue.
I have a beef, not with UCS--which is a great organization--but with the implications that can easily be drawn from such a study, specifically the implication that anyone, anywhere, should feel free to go ahead and buy a gasoline auto if the utility system in the region depends heavily on coal. Don't do it!
I say not so, and here's why. The problem with carbon emissions from an EV, such as they are, is not inherent with the EV, it's a problem with the utility system, and a problem that can actually be fixed, by the utility building or purchasing more renewable energy (solar, wind, hydro, biomass) power plants. The problem with carbon emissions from a gas auto is inherent with the auto, and you're investing in a (small) piece of infrastructure that will never get better until it goes to the junkyard at the end of its useful life, 10 to 20 years from now.
The Times article, and the UCS study itself, suggest how easy it is to misread the issue. The article ends as follows: "'To prevent the worse consequences of global warming,' the report concludes, 'the automotive industry must deliver viable alternatives to the oil-fueled internal combustion engine, i.e., vehicles boasting zero or near-zero emissions.'" (emphasis added) But what about the utility industry? It's remarkable that it isn't mentioned, given the subject of the study. More importantly, it's remarkable because using electricity to break into the transportation energy market is a huge potential opportunity for electric utilities to expand their business. Geez.
(I've had at least one argument on the Web about a closely related topic. The people involved were very environmentally conscious, and dissing the idea of driving entirely for the same reason, saying that bicycling is the only way to go. In essence, I told them, "If you want to see gasoline autos for the indefinite future, just keep belittling EVs and that is what you will get.")
Luckily, it turns out that our region (northeastern U.S.) has a relatively low-carbon generating mix, and so an EV tops the best hybrid, which means there is a good chance we will pop for one. To me, it's a no-brainer, not only because of the reasoning above, but because buying or leasing it helps demonstrate there is a market and sends a message to other drivers who see it around town.
The one (very minor) downside? Owning an EV will boost our electric bills a tad, just as we are beating them into submission with a backyard solar system. Still, that's a minor issue, as driving an EV costs roughly 1/4 as much per mile as driving a gasoline auto.
Sunday, March 24, 2013
Misinformation in Vermont's wind power debate
Vermont's State Senate is currently debating a bill, S. 30, that would impose a set of new restrictions on the siting of renewable energy facilities in the state. I'm opposing this bill, which would throw another roadblock in the path of efforts to reduce greenhouse gas emissions. If you would like more information on this debate, a good basic resources is the Vermont Public Interest Research Group's Support Wind page.
This specific post responds to a post on the Norwich, Vermont, town listserve by Ms. Clare Holland, of Sharon, Vt., who is a supporter of S. 30. I've responded briefly on the listserve, but said I'd add some comments here for those who want more detail.
A few errors and omissions from Ms. Holland's posting:
- Ms. Holland makes much of the fact that only 4% of Vermont's carbon dioxide emissions are from electricity generation. In fact, consumption of electrical power in Vermont accounts for much more than that, because all marginal consumption is provided by fossil plants elsewhere in the region. Vermont uses/consumes 5.6 billion kilowatt-hours of electricity a year, which at the marginal New England emissions rate of 0.943 pounds per kilowatt-hour equals 2.64 million tons of CO2 attributable to electricity consumption in Vermont. Adding that to the 6.3 million tons of CO2 actually emitted in Vermont means electricity consumption accounts for 30% of Vermont’s CO2 emissions, not 4%. The cost of operating a wind farm is very low, so whenever the wind is blowing, the electricity it generates displaces electricity from the most expensive (usually oldest and most polluting) power plant on the New England ISO utility system.
- New renewable energy power plants in Vermont are already subject to the same aesthetic and other standards as are contained in Act 250. The key difference is that under Section 248, the Act-250-like permitting regulation that governs power plants and infrastructure, there is no local veto. Why? Because a balance must be struck between finding a way to produce the energy we all need and the rights of people to object to projects "in their back yard." Section 248 represents that balance, negotiated over a number of years through the legislative process. Now the State Senate, after a few weeks of discussion which have been notable for the circulation of wild misinformation about wind, proposes to toss that process out the window.
- With respect to bird fatalities at wind farms, the answer is simple: wind farms are not a threat to birds in general. A recent study estimates that U.S. cats kill 2.4 billion birds a year, while a summary of studies from more than 100 wind farms results in a finding that less than 200,000 die as a result of colliding with wind turbines. In short, cats kill more birds in one hour than all U.S. wind farms do in a year.
Additional resources:
Article from Green Mountain Daily that explains just how thorough Vermont's existing siting process is
Opinion article on S. 30 from Johanna Miller, energy program director at Vermont Natural Resources Council
Monday, September 3, 2012
Indispensable Arctic sea ice graph
A lot of ingenuity has gone into graphics displaying various ways of measuring the Arctic sea ice death spiral. There are graphs depicting sea ice extent (total area within the outer boundaries of the ice pack), area (extent minus the gaps of water), and volume. One can find web pages that specialize in mapping past and current measurements of one of these parameters against different trend lines, in an attempt to get a feel for when the ice will disappear entirely, or almost entirely, during the summer. There is even one that shows the death spiral as a ... spiral ... using a polar coordinate graphing scheme.
I personally find the most useful graph, though, to be this simple bar chart of sea ice volume. Bar charts are very familiar, so it's easy to understand at a glance, and when it comes to sea ice, volume seems to me like the most important measurement. Sea ice extent and area "recovered" rapidly last year to "near normal levels," but the all-time record low in both of those parameters this year makes it clear that much of the ice growth last winter was a very thin coating--which is where volume comes in.
Thanks to Lawrence Hamilton of the University of New Hampshire for permission to reproduce it.
What does this graph tell us?
Currently, volume stands at 3,600 cubic kilometers (cu-km), about half what it was as recently as 2008 (7,100 cu-km) and just over one-fifth what it was in 1979 (16.9 cu-km). Records begin in 1979 because this set of data is from satellite monitoring, which began in that year.
Also, the trend line is obviously sharply down. If you imagine a line connecting the 1979 number and this years, it looks as though it will reach zero sometime within the next decade, perhaps 2018.
A quick review of some basics concerning Arctic sea ice:
- Its melting will not affect sea level rise, because the ice is floating and displacing the same mass of water as is created when it melts.
- Its melting is, however, likely to continue because of the positive feedback loop created when ice, which reflects sunlight, melts to expose open water (less reflective), leading to warmer temperatures.
- Its melting may also be leading to changes in the jet stream and in the weather the jet stream affects further south.
You can learn much, much more on the topic from the Arctic Sea Ice blog, which I cannot recommend too highly as a resource.
I personally find the most useful graph, though, to be this simple bar chart of sea ice volume. Bar charts are very familiar, so it's easy to understand at a glance, and when it comes to sea ice, volume seems to me like the most important measurement. Sea ice extent and area "recovered" rapidly last year to "near normal levels," but the all-time record low in both of those parameters this year makes it clear that much of the ice growth last winter was a very thin coating--which is where volume comes in.
Thanks to Lawrence Hamilton of the University of New Hampshire for permission to reproduce it.
What does this graph tell us?
Currently, volume stands at 3,600 cubic kilometers (cu-km), about half what it was as recently as 2008 (7,100 cu-km) and just over one-fifth what it was in 1979 (16.9 cu-km). Records begin in 1979 because this set of data is from satellite monitoring, which began in that year.
Also, the trend line is obviously sharply down. If you imagine a line connecting the 1979 number and this years, it looks as though it will reach zero sometime within the next decade, perhaps 2018.
A quick review of some basics concerning Arctic sea ice:
- Its melting will not affect sea level rise, because the ice is floating and displacing the same mass of water as is created when it melts.
- Its melting is, however, likely to continue because of the positive feedback loop created when ice, which reflects sunlight, melts to expose open water (less reflective), leading to warmer temperatures.
- Its melting may also be leading to changes in the jet stream and in the weather the jet stream affects further south.
You can learn much, much more on the topic from the Arctic Sea Ice blog, which I cannot recommend too highly as a resource.
Wednesday, August 29, 2012
As the solar odometer turns
We have a new residential solar electric (PV, photovoltaic) system installed about a month ago, and its "odometer" will soon turn over the 5 in 500 kilowatt-hours (kWh) of electricity generated.
It's pretty impressive, just in a mechanical (or rather, non-mechanical) sense. It just sits there. Nothing seems to happen, but the kWh generated daily continues to rise. No muss, no fuss. Pretty neat.
But I digress. The reason for this post was to say something about what 500 kWh will represent, when we get there later today or tomorrow.
In terms of energy, it's the equivalent of 15 gallons of gasoline, or enough to drive one of our hybrid autos about 675 miles.
In terms of generating electricity, the numbers are bigger, because the combustion process for fossil fuels wastes energy. 500 kWh is equivalent to burning about 500 pounds of coal, or 35 gallons of diesel oil (New England, where we are located, still burns plenty of diesel oil to generate electricity).
In terms of carbon dioxide (CO2) emissions, the New England utility system gives off about one pound of CO2 per kilowatt-hour of electricity, so our 500 kWh means about 500 pounds of carbon dioxide has been kept out of the atmosphere.
So what? Well, that's where the numbers get truly impressive, because of the very long life and heat-trapping effect of carbon dioxide. In a post on his blog, Quark Soup, science journalist David Appell quotes David Archer's book, The Long Thaw: How Humans Are Changing the Next 100,000 Years of Earth's Climate, as follows:
"If we add up the total amount of energy trapped by CO2 from the gallon of gas over its atmospheric lifetime, we find that our gallon of gasoline ultimately traps one hundred billion (100,000,000,000) kilocalories of useless and unwanted greenhouse heat."
Burning one gallon of gasoline results in the emission of 19.6 pounds of CO2. That means that one pound of CO2, over its lifetime, traps 100 billion kilocalories divided by 19.6, or 5 billion kilocalories.
Now, I don't know about you, but I don't use kilocalories much on a day-to-day basis, so, how much energy is that? Using the handy Google converter for units of measure, I find that it is 2 x 10 to the 13th (10e13) joules--still not a very meaningful quantity. However, one Hiroshima-size atomic bomb releases 63 x 10e12 joules, and one pound of CO2 traps 2 x 10e13 (20 x 10e12) joules. In other words, just three pounds of CO2 added to the atmosphere, over its lifetime, traps as much heat as released by the Hiroshima bomb (a unit of measure Mr. Appell calls the "hiro").
This in turn means that, in a little over a month, our residential solar system has kept enough CO2 out of the atmosphere to trap the equivalent, over time, of the heat that would be released by 167 Hiroshima bombs.
(It also says a lot about how much heat you're adding, over time, to the climate system with every gallon of gas--about 7 Hiroshima bombs' worth--and why it's silly to claim that the billions of tons of carbon dioxide we're adding to the atmosphere each year have no impact on the climate. But that's another blog post.)
I expect to use these numbers more in the future, in other posts and in comments on the Internet, so if you find any errors, please let me know (Mr. Appell has made the same offer, and nothing has turned up yet).
UPDATE (Sept. 8, 2012): The odometer now stands at 626 kWh, which means we have passed another minor milestone--the first barrel of oil equivalent (BOE). Burning a barrel of oil generates about 600 kWh--and produces 940 pounds (almost half a ton) of carbon dioxide.
It's pretty impressive, just in a mechanical (or rather, non-mechanical) sense. It just sits there. Nothing seems to happen, but the kWh generated daily continues to rise. No muss, no fuss. Pretty neat.
But I digress. The reason for this post was to say something about what 500 kWh will represent, when we get there later today or tomorrow.
In terms of energy, it's the equivalent of 15 gallons of gasoline, or enough to drive one of our hybrid autos about 675 miles.
In terms of generating electricity, the numbers are bigger, because the combustion process for fossil fuels wastes energy. 500 kWh is equivalent to burning about 500 pounds of coal, or 35 gallons of diesel oil (New England, where we are located, still burns plenty of diesel oil to generate electricity).
In terms of carbon dioxide (CO2) emissions, the New England utility system gives off about one pound of CO2 per kilowatt-hour of electricity, so our 500 kWh means about 500 pounds of carbon dioxide has been kept out of the atmosphere.
So what? Well, that's where the numbers get truly impressive, because of the very long life and heat-trapping effect of carbon dioxide. In a post on his blog, Quark Soup, science journalist David Appell quotes David Archer's book, The Long Thaw: How Humans Are Changing the Next 100,000 Years of Earth's Climate, as follows:
"If we add up the total amount of energy trapped by CO2 from the gallon of gas over its atmospheric lifetime, we find that our gallon of gasoline ultimately traps one hundred billion (100,000,000,000) kilocalories of useless and unwanted greenhouse heat."
Burning one gallon of gasoline results in the emission of 19.6 pounds of CO2. That means that one pound of CO2, over its lifetime, traps 100 billion kilocalories divided by 19.6, or 5 billion kilocalories.
Now, I don't know about you, but I don't use kilocalories much on a day-to-day basis, so, how much energy is that? Using the handy Google converter for units of measure, I find that it is 2 x 10 to the 13th (10e13) joules--still not a very meaningful quantity. However, one Hiroshima-size atomic bomb releases 63 x 10e12 joules, and one pound of CO2 traps 2 x 10e13 (20 x 10e12) joules. In other words, just three pounds of CO2 added to the atmosphere, over its lifetime, traps as much heat as released by the Hiroshima bomb (a unit of measure Mr. Appell calls the "hiro").
This in turn means that, in a little over a month, our residential solar system has kept enough CO2 out of the atmosphere to trap the equivalent, over time, of the heat that would be released by 167 Hiroshima bombs.
(It also says a lot about how much heat you're adding, over time, to the climate system with every gallon of gas--about 7 Hiroshima bombs' worth--and why it's silly to claim that the billions of tons of carbon dioxide we're adding to the atmosphere each year have no impact on the climate. But that's another blog post.)
I expect to use these numbers more in the future, in other posts and in comments on the Internet, so if you find any errors, please let me know (Mr. Appell has made the same offer, and nothing has turned up yet).
UPDATE (Sept. 8, 2012): The odometer now stands at 626 kWh, which means we have passed another minor milestone--the first barrel of oil equivalent (BOE). Burning a barrel of oil generates about 600 kWh--and produces 940 pounds (almost half a ton) of carbon dioxide.
Sunday, August 26, 2012
Mything in action: Deniers and 'Antarctic warming'
I saw it on Twitter today, so it must be true: several posts in succession, all from self-avowed defenders of the Constitution, liberty, blah blah, etc., to the effect that the "Antarctic has been warming for 600 years."
Hmm, I thought as I added these individuals to my "disappear" list on TweetDeck (a time- and annoyance-saving strategy that makes their future tweets invisible to me), I wonder what that is all about?
As I continued to comb the Web for global warming items to tweet, I came across an article in an Australian publication, Crikey, titled "Antarctic melt alarm as scientists find 'very unusual' warming." Mystery solved.
The article's lead paragraph: "Scientists have drilled 364 metres into ice to complete the first ever comprehensive temperature record of the Antarctic Peninsula — and they’ve found evidence of 'very unusual' and dramatic warming over the last century." [emphasis added]
The article goes on to say, indeed, that the peninsula has been warming slowly for 600 years, but takes some pains to explain the reason for concern:
"The research showed that the Peninsula has seen a rapid warming over the past 100 years, but that this has also come on top 600 years of more gradual, natural warming in the region ...
"The leader of the research expedition, Dr Robert Mulvaney from the British Antarctic Survey, said: 'The exceptionally fast warming over the last 100 years came on top of a slower natural climate warming that began around 600 years ago — well before the industrial revolution — so it is possible that we are now seeing the combination of natural and man-made warming in this area.'
Hmm, I thought as I added these individuals to my "disappear" list on TweetDeck (a time- and annoyance-saving strategy that makes their future tweets invisible to me), I wonder what that is all about?
As I continued to comb the Web for global warming items to tweet, I came across an article in an Australian publication, Crikey, titled "Antarctic melt alarm as scientists find 'very unusual' warming." Mystery solved.
The article's lead paragraph: "Scientists have drilled 364 metres into ice to complete the first ever comprehensive temperature record of the Antarctic Peninsula — and they’ve found evidence of 'very unusual' and dramatic warming over the last century." [emphasis added]
The article goes on to say, indeed, that the peninsula has been warming slowly for 600 years, but takes some pains to explain the reason for concern:
"The research showed that the Peninsula has seen a rapid warming over the past 100 years, but that this has also come on top 600 years of more gradual, natural warming in the region ...
"The leader of the research expedition, Dr Robert Mulvaney from the British Antarctic Survey, said: 'The exceptionally fast warming over the last 100 years came on top of a slower natural climate warming that began around 600 years ago — well before the industrial revolution — so it is possible that we are now seeing the combination of natural and man-made warming in this area.'
"What this means is that climate change is adding significant extra pressure to the Antarctic Peninsula ice sheets that were already seeing some strain from the natural warming in the region." [emphasis added]
Just remove that context and presto, you have a tweet that implies global warming is nothing to worry about, when exactly the opposite is true.
Why now? Presumably in a transparent and rather desperate attempt to spread a counter to the news that Arctic sea ice melt has hit a new record.
(Disclaimer: I have nothing against the Constitution and liberty--they're great! But I do wonder sometimes why people act as though they are part of a valiant few who think so.)
Arctic sea ice and 'natural cycles'
It's a favorite climate change denier meme: "It's all natural cycles--the climate is always changing."
So, here is one of the things that is new. A blogger has taken a graphic from a 2011 scientific paper (Kinnard et al) reconstructing the extent of Arctic sea ice for the past 1,450 years and updated it to show actual observations of the last 12 years:
(Minor caveat: This was posted to the Skeptical Science blog and an astute reader pointed out that it is exaggerated slightly--because of the time of year at which measurements were compared, 2012 should actually be about five dashes higher than it is in the graphic.)
I cannot help but note that this is yet another version of the "hockey stick" shape that shows up in many areas of climate research and that results from the speed with which humanity is impacting the Earth's climate (see, e.g., this similar graphic, in reverse, of surface temperatures of Lake Tanganyika over a similar time frame).
Anyone out there think the above graphic looks like a natural cycle? If so, please send me a small sample of what you are smoking--I'd like to give it a try.
UPDATE 8/26/12: Joe Romm's excellent Climate Progress blog has an article today titled "Why the Arctic sea ice death spiral matters" that includes the graphic above (minus the extension to 2012) and much more.
So, here is one of the things that is new. A blogger has taken a graphic from a 2011 scientific paper (Kinnard et al) reconstructing the extent of Arctic sea ice for the past 1,450 years and updated it to show actual observations of the last 12 years:
(Minor caveat: This was posted to the Skeptical Science blog and an astute reader pointed out that it is exaggerated slightly--because of the time of year at which measurements were compared, 2012 should actually be about five dashes higher than it is in the graphic.)
I cannot help but note that this is yet another version of the "hockey stick" shape that shows up in many areas of climate research and that results from the speed with which humanity is impacting the Earth's climate (see, e.g., this similar graphic, in reverse, of surface temperatures of Lake Tanganyika over a similar time frame).
Anyone out there think the above graphic looks like a natural cycle? If so, please send me a small sample of what you are smoking--I'd like to give it a try.
UPDATE 8/26/12: Joe Romm's excellent Climate Progress blog has an article today titled "Why the Arctic sea ice death spiral matters" that includes the graphic above (minus the extension to 2012) and much more.
Saturday, August 25, 2012
Meltdown continues: 2012 breaking Arctic records
Not too long ago (July 17, to be exact), I wrote here:
"'7. The Arctic Ocean is projected to become nearly ice-free in summer within this century, likely within the next thirty to forty years.' [It's not hard to find people on the Web, who know what they are talking about, who believe this will happen before 2020. While 2012 is, at this writing, on a record pace for Arctic sea ice melt, it remains to be seen whether a new ultimate summer low will result. What we can say, however, is that there has been no recovery from the 2007 summer low, which was sharply lower than the summer lows in previous years going back to 1979 (when measurements began). You can check out sea ice area through this wonderful interactive graphic, which provides data by day and year. You can "erase" years by clicking on them at the right, and if you erase back to 2007, you will see that the summer low was roughly 3 million square kilometers, almost exactly a whopping 25% below the low of 4 million reached in 2006.]"
While all the results are not in yet, and won't be until the potential melting season ends next month, 2012 has now erased the 2007 lows for Arctic sea ice area. As of today, the ice area reported in Cryosphere Today graphic linked to above stands at 2.65 million square kilometers, well below the '07 low of 2.92 million. The Arctic Sea Ice blog, which appears in the blog list on the right side of this page, has very deep coverage of Cryosphere Today and the several other ongoing measurements of sea ice (extent, area, volume, etc.). All of the groups measuring except one are now reporting new records.
What does this mean to us? Joe Romm explores the question in a blog at Climate Progress (otherwise known as the climate section of ThinkProgress): "In particular, a 2012 Geophysical Research Letters study, “Evidence linking Arctic amplification to extreme weather in mid-latitudes,” finds that the loss of Arctic ice favors “extreme weather events that result from prolonged conditions, such as drought, flooding, cold spells, and heat waves.”
"'7. The Arctic Ocean is projected to become nearly ice-free in summer within this century, likely within the next thirty to forty years.' [It's not hard to find people on the Web, who know what they are talking about, who believe this will happen before 2020. While 2012 is, at this writing, on a record pace for Arctic sea ice melt, it remains to be seen whether a new ultimate summer low will result. What we can say, however, is that there has been no recovery from the 2007 summer low, which was sharply lower than the summer lows in previous years going back to 1979 (when measurements began). You can check out sea ice area through this wonderful interactive graphic, which provides data by day and year. You can "erase" years by clicking on them at the right, and if you erase back to 2007, you will see that the summer low was roughly 3 million square kilometers, almost exactly a whopping 25% below the low of 4 million reached in 2006.]"
While all the results are not in yet, and won't be until the potential melting season ends next month, 2012 has now erased the 2007 lows for Arctic sea ice area. As of today, the ice area reported in Cryosphere Today graphic linked to above stands at 2.65 million square kilometers, well below the '07 low of 2.92 million. The Arctic Sea Ice blog, which appears in the blog list on the right side of this page, has very deep coverage of Cryosphere Today and the several other ongoing measurements of sea ice (extent, area, volume, etc.). All of the groups measuring except one are now reporting new records.
What does this mean to us? Joe Romm explores the question in a blog at Climate Progress (otherwise known as the climate section of ThinkProgress): "In particular, a 2012 Geophysical Research Letters study, “Evidence linking Arctic amplification to extreme weather in mid-latitudes,” finds that the loss of Arctic ice favors “extreme weather events that result from prolonged conditions, such as drought, flooding, cold spells, and heat waves.”
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