Author Archives for brentn

Craig Venter wants to save the world

No one grandstands quite like Craig Venter. Whether its leading a team racing the government to the first human genome sequenced, succeeding, or admitting that his team beat the government by sequencing his own genome, this guy has style like few others in science. And while physicists at least have the reputation of having large egos installed as part of their graduate training, Venter’s ego is apparently physicist-sized, at least according to Wired and Forbes.

That being said, there is something phenomenally inspiring about the folks who have no shame about tackling the really big problems. This is a constructive sort of hubris, the kind that Larry Wall correctly identified as a virtue. Venter’s glorious hubris was on display this week at the TED conference, where he announced that he was working on a project to engineer a bacteria that turns carbon dioxide into methane and octane and that he expects results within 18 months on these fourth generation fuels.

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More on biofuels vs. greenhouse gases

In regards to my previous post on the recent studies on biofuels, WorldChanging has posted an article about the issue, citing a study released by the Sierra Club as well as the Science report. The WorldChanging blog post mentions that the Science report “reinforced the urgency of moving to second-generation biofuels.”

In considering this topic, I think something else extremely valuable is coming out of the biofuel boom. We’re learning how to quickly estimate environmental costs.

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More on porous asphalt

I posted a quick note earlier about installing porous asphalt in a green community in Oregon. In that note, I made an offhand comment questioning the water quality coming off the road. After posting the article, I also wondered if the lifetime of the surface would be shorter in areas prone to freezing weather due to the expansion and contraction of ice in the pores.

It turns out that had I been less lazy in doing my research, I’dve had all these questions answered much more quickly. I just found a great article on porous asphalt that covers a lot of topics, including water quality (82% removal efficiency for organic carbon) and lifetime in freezing weather (longer than standard asphalt).

Additionally, the article points out that the porosity allows for less use of salts for deicing and that:

The water drains through the pavement and into the bed below with sufficient void space to prevent any heaving or damage, and the formation of “black ice” is rarely observed. The porous surfaces tend to provide better traction for both pedestrians and vehicles than does conventional pavement. Not a single system has suffered freezing problems.

Pretty darned cool, if you ask me. One has to ask what the factors are that are keeping this from being installed in every new parking lot being built. Undoubtedly, the subsurface strata affect the design – this is also covered in the article – but I suspect strong that the major factor is simply ignorance.

On a lighter note, the best quote from the article is this one: “Fortunately, even without regular maintenance, the systems continue to function (we routinely send graduate students and recent hires out in hurricanes to confirm this).”

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Does the blame fall on biofuels

In the alternative energy circles, a recent Science magazine online article published by a group from Minnesota has been making a lot of waves in the media. This article from the Seattle Times is typical of the coverage. There are a couple of issues with both the article and the coverage of the article that I’d to point out.

First, let me tackle the article. While no one will argue that corn ethanol is an extremely poor choice for a biofuel feedstock, it is also inarguable that the article focused on current biofuel technology. This implicitly assumes that all new biofuels will be roughly equally bad for the environment. Clearly, this is not the case, since algal-derived biodiesel and similar biomass-derived fuels will not contribute equally to global warming through the destruction of ecosystems. The article also assumed by implication that biofuels are the primary driver behind conversion of ecosystems to cropland. Past data would indicate that this is almost certainly not the case, since slash-and-burn was prevalent in the Amazon basin well before biofuels become a cause celebre. The issues around land use in the developing world would exist with or without biofuels contributing, since there is rarely an incentive for the governments who control these lands to preserve them. Rain forests do not yield significant economic benefit to those who live near them. All the biofuel boom has done is exacerbate the situation. Hopefully, this will bring attention to dealing with the root causes of the destruction of these ecosystems – namely, food security and poverty.

The media has been largely guilty of indulging in shrill hachet jobs on the nascent biofuel industry based on this article. I am certainly not implying that the authors of the Science report intended this; rather, I think that the natural tendency to want to take potshots at large targets is to blame here. Nevertheless, I think its important that people interested in short term energy development continue to work on capturing energy from biomass. With any luck, we’ll solve both the petroleum problem and the disappearing ecosystems problem at the same time.

In Chicago

I’m in Chicago this week on business. Things started off with a cancelled flight for both me and one of my teammates (two separate flights). Then, our first trial completely bombed, forcing me to revise the experimental plan somewhat. And to top it off, the 4th guy on the team who was coming had 3 flights cancelled or delayed, making him 24 hours late. Go Chicago-O’hare!

We’re up and going now and I’m sitting in the lab working on a new model for the data we’re collecting while I watch the equipment run.

Porous streets

After reading this post from WorldChanging, I wondered a bit about the wisdom of porous pavement. Sure, I understand the issues that are caused by stormwater runoff, but I’m a little concerned about what gets washed off the streets through the pores in the pavement.

There are probably good ways to handle this, including beds of Stropharia mushrooms on either side of the road to mycoremediate the waste water stream or even a filter layer underneath the pavement.

I also wonder what is actually underneath that pavement. Is it the sand and gravel bed that typically underlies roadways? Or is it something else more porous? The percolation through a layered gravel bed might reduce the pollution in the water that passes through.

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Upgrading from an oil furnace to a heat pump

Last fall, when I was at MRS, the 40 year old oil furnace that had heated our home finally died. The diagnosis: cracked heat exchanger. We’d discussed this possibility a few times, trying out some scenarios. At the time of the incident, our current thinking was either a high-efficiency oil furnace capable of burning biodiesel or a heat pump. The folks at McNutt Service Group, the contractor we decided to work with, quoted us around $4000 for the oil furnace and about $6300 for the heat pump. The heat pump we had selected was a slightly above-average Trane model (16 SEER, 9.0 HSPF), which (along with the new air-handling system) we felt would give us the best deal in terms of efficiency and cost. After much debate, we decided to go with the heat pump for a variety of reasons. the most salient of these was the operating cost. I ran some rough numbers and estimated that over a 20 year lifespan of each unit, I should save around $6000 using the heat pump, based on a 3% per year increase in the cost of heating oil and a 1.5% increase in the cost of a kWh of electricity.

After receiving my first electrical bill that included a full month of the heat pump, I realize I may have underestimated the savings. The amount had only increased by about $35. At first, I thought that this month might have been warmer than usual, and in fact there were some warm days in the month. There were also several nights of temperatures in the teens. The National Weather Service’s climate data page did not indicate that the highs and lows during the month were excessive in either way (average temperatures 3-5 degrees above normal in December and a roughly equal number of days above and below in January.) With that, I was reasonably satisfied that the bill represented a typical January bill. A quick check back through my financial records showed me that from Oct. 2006 to Oct. 2007, I’d spent $766 on heating oil.

Going back to my spreadsheet, I plugged those differences in. Still not trusting the $35 number, I assumed that over the 6 month “winter” period, I’d average $50 more a month, for a total of $300. This number I assume is the cost of heating with electricity. Plugging in the growth rates I mentioned earlier, I set about determining my time to payback over an oil furnace. It’s less than 5 years to save the $2300 difference between the two units. But this really isn’t a good comparison – the new oil furnace would be much more efficient than the ancient Lennox furnace we had. The oil furnace we were quoted on was 90% efficient. Though I don’t have the numbers for certain, I’m estimating that the old furnace was no more than 70% efficient. Using that to adjust the cost of fuel oil, I recomputed the time to payback and got 7 years. Still, not bad at all. Assuming the growth numbers hold, I’ll save around $9000 (in today’s dollars) over the lifetime of the heat pump. And this doesn’t even count the savings in the summer of the 16 SEER heat pump over the old 11 SEER air conditioning unit that came with the house.

Bottom line for us was that the heat pump is looking to be a very good investment. And if folks like Nanosolar make it ultra cost-effective to put photovoltaics on every roof, the heat pump will be an even better decision.

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Quote of the year

I’ve been reading “What We Believe but Cannot Prove”, by John Brockman. Its a compilation of short essays by some of the world’s leading thinkers, covering that eponymous topic. One of the best responses comes from Seth Lloyd, professor of Mechanical Engineering at MIT.

I believe in science. Unlike mathematical theorems, scientific results can’t be proved. They can only be tested again and again until only a fool would refuse to believe them.
I cannot prove that electrons exist, but I believe fervently in their existence. And if you don’t believe in them, I have a high voltage cattle prod I’m willing to apply as an argument on their behalf. Electrons speak for themselves.

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