Michael Morrison

Flying Offsets

Joe Romm claimed that the real name for carbon offsets is “carbon rip-offsets” because they are all rip-offs. But the high energy-to-weight and rapid-fueling requirements for aviation fuel means that there are currently no usable substitutes, and there is very little we can do to reduce the carbon emissions of flying other than to not fly. Isn’t there some way we can confidently mitigate our air travel emissions?

Ultimately, a true offset will either put carbon back into the ground in a long-lasting form such as coal, oil, or charcoal; or it will reduce the amount of carbon that would otherwise have been dug-up and burned. The first is hard to do, and the second is hard to verify. But M. Sanjayan suggested an approach that makes good sense to me: giving away energy efficient lighting on his trips. The bulbs offset carbon by reducing the energy used to provide light, increasing what I call “energy performance”; providing the same energy services but with less energy. He suggested CFL’s, but LEDs are now in mainstream production and offer an even better solution.

I wondered, how many LEDs would I have to buy and give away to offset a given flight? The amount of carbon dioxide produced in the generation of electricity varies around the world, but in the USA the EPA tells us we average about 0.55 kg per kWh. On a visit to my local hardware store this week, I found 60 watt replacement LEDs for $13. These use only 9.5 watts of electricity and produce the same light as a 60 watt incandescent bulb. They are rated to last 25,000 hours.

We see that over 25,000 hours, a 60 watt bulb will use 1,500 kWh of electricity and the 9.5 watt LED will use 238; a difference of 1,262 kWh. Using the U.S. average of 0.55 kg per kWh, this means that replacing a 60 watt incandescent bulb with this LED will reduce electric power carbon dioxide emissions by 694 kg.

How much carbon dioxide do I emit on a flight? Terrapass, a seller of “offsets”, provides a calculator to estimate this number. They indicate that for a Los Angeles / New York roundtrip, each passenger creates 873 kg of carbon dioxide emissions.

It looks like I can offset my carbon emissions from a round-trip cross-country flight by buying and giving away two 9.5 watt, 60 watt replacement, LEDs to someone who will use them to replace incandescents. A significant virtue of this approach is that it is verifiable to me: I know I bought the bulbs; I know I gave them to someone who installed them; and I know they will reduce electric power consumption while providing the recipient with the same energy service (lighting) that they previously enjoyed and saving on electric bills in the bargain. I don’t have to worry about whether the offset company is honest, or how much of my donation is actually going towards an offset, or whether it is really an offset. And, as Sanjayan says, it’s a fun way to make friends at your destination.

The Great Battery Race

Since the discovery of fire, energy has been hard to obtain and easy to store. Wood had to be cut down, cut up, dried, and hauled to where it was going to be burned. But once you had it, nothing special was required: just let it sit there through cold or hot temperatures, in sunlight or shade. Fossil fuels are similar: they must be found, extracted, and refined. But once obtained, they can be stored in piles or tanks with no special needs. Our thinking has been organized around this historically universal fact. Our focus is on “how will we get it?”, more than on “how will we store it?”.

But the times they are a changing. While the price of fossil fuels inexorably increases (we extract the easy ones first and then, as they run out, must move on to ever more difficult-and-costly-to-extract sources), the cost of wind and photovoltaic power is steadily decreasing as we improve manufacturing and technology, and realize the economies of scale. Barclay’s recently downgraded the entire U.S. electric industry because of this trend, and the California ISO reports that there are times of the day when they have more electricity in the grid than they can use; they can’t give it away. We are entering a time when wind and photovoltaic energy is relatively easy, and almost free, to obtain but—so far—maddeningly difficult to store.

As a result, a great battery race has been engaged. While lithium-ion batteries appear to be the winner when weight matters, such as for cars and phones, they appear to be too expensive for storing electricity on a grid, or even home-use, scale.

There are many entrants in this race, all trying to build batteries that are inexpensive, work well with the grid, and can be manufactured at scale. Weight doesn’t matter, price does. Two of my favorites are Donald Sadoway’s Ambri, and Aquion Energy out of Carnegie Mellon. Both of these start-ups are using inexpensive, abundant raw materials and simple, rapidly-scalable manufacturing. Both already have batteries in service. It won’t be long before such batteries are ubiquitous and the combination of easy-to-obtain energy and inexpensive storage dramatically changes the energy industry. And, for the first time in human history, changes how we think about obtaining and storing energy.

We have seen how effective policy has had profound, positive effects on the atmosphere and our economy. And while we have failed to enact similar policy efforts for greenhouse gases, it appears that simple economics may lead to the needed result of leaving fossil fuels unburned and in the ground.

In the meantime, the Great Battery Race will be fun to watch and will make the winners rich. Very rich.

Rapid Change - For The Better

We now know that the general term “climate change” includes many different aspects, from changes in rain and snowfall patterns, to local increases and decreases in temperature, and more. One of the discoveries we have made is that some aspects, like increased carbon dioxide levels, are long-lasting and others, like sulfur emissions, are removed from the air in a matter of a few years.

One of the implications of these fast and slow changing pollutants is that the sooner we start on the long-lasting ones, like carbon dioxide, the easier it will be and the greater our success. But another implication is that there are changes we can make that will have an near-immediate effect, and offering a nice, instant-gratification hit in the process.

Ground level ozone results when fossil fuel combustion products are exposed to sunlight. Without the combustion products, ozone does not form, and if combustion products are reduced, ozone drops off within days. Ground level ozone is very reactive worsening, and even causing, respiratory illnesses. It also damages plants.

Sachin Ghude and colleagues just estimated the crop losses in India resulting from fossil-fuel fueled, ground level ozone. They estimate that 5.6 million tons—5.6 billion kilograms—of wheat and rice were lost from ozone damage in 2005; enough to feed about 94 million people.

Just one of the many health, economic, and security costs of climate change, policies that reduce fossil fuel emissions would result in instant, significant, increases in crop yields in India.