Archive for February, 2010

Electricity in a Box: Bloom Energy Servers

February 25, 2010

Lots of publicity over the past few days about the new BLOOM BOX ‘Energy Server’ – an on-site source of electricity powered by a natural gas burning fuel cell. Details are awfully sketchy, but Bloom Energy CEO K.R. Sridhar paints a tantalizing vision of an off-grid future built around his energy server concept. A couple of things seem clear:

1. The Bloom Box appears to be a Solid Oxide Fuel Cell, technology that has been in the commercial sphere for close to a decade. A number of companies claim some commercial SOFC expertise; WIKI has a good intro to SOFC.

Sridhar implies the Bloom version of SOFC makes substantial improvements over current products, but here the details from Bloom fade out. Have they achieved a breakthrough in conversion efficiencies and waste heat recovery? In manufacturing costs? In maintenance and longevity?

If you assume that the 100kW unit spec’d on the Bloom Energy website is the same as the $800k commercial unit they discuss, then the per-kW installed cost of the Energy Server system would be more expensive (but not too far out of the same ballpark) as a fully installed, grid-integrated (but much smaller) residential solar electric system. Not bad for the first shot out of the box, but still a long way to go before Energy Servers will replace your local electric company.

2. Bloom’s primary energy source is a hydrocarbon gas – natural gas in the demonstration cases, but LPG, syn gas or their bio-derived equivalents would also do. In any case, it’s a 2-step chemical process:
– Catalytically ‘burning’ the gas with atmospheric oxygen to produce Hydrogen and CO2
– Electrolytically combining the hydrogen with more oxygen to produce electricity and water
One potential but real advantage of Bloom’s modular SOFC approach is its ability to conveniently recover waste heat, at a usefully high temperature.

The inconvenient detail that prevents this from being a totally green technology is, of course, CO2, the unavoidable result of using a carbon based primary fuel. Hydrogen fuel cells provide the dream-world answer, but until we have a huge, economically viable of source of Hydrogen that doesn’t depend on a carbon-based source, the hydrogen economy will remain just that – a pleasant day dream.

3. Bloom Energy and its venture capital backers have lined up an impressive array of corporate demonstration projects and high profile supporters, and they’re orchestrating an effective publicity blitz – which will surely boost an IPO somewhere (probably not too far) down the road.

They deserve some applause: Bloom, along with the rest of the SOFC community, have been working at the this for a decade, and the R&D cycle is beginning to yield results that the marketplace can put through the economic feasibility wringer.

But they deserve some skepticism, too. We will need a lot more experience – and a lot more solid data from Bloom – before we can start to sort the real story from the hype.

So the best advice is patience. Even if we assume that Bloom truly has made some startling breakthroughs in cost, efficiency and practicality, moving the technology from gee-whiz demonstrations to day-in day-out commodity will not be a quick or easy exercise.

NOTE: Most of the current news stories – including the CBS 60 Minutes clip – have a flavor of ‘Hey, guys, look at this cool press release!’ Here are a couple that dig a little deeper – the Guardian article is especially good.

Bio-Diesel from Algae – Good Idea or Bad Dream?

February 11, 2010

Bio-diesel from algae – sounds like a winner! But not so fast —

Researchers from the University of Virginia’s Department of Civil and Environmental Engineering have found there are significant environmental hurdles to overcome before [algae-based] fuel production ramps up …. The U.Va. research, just published in the journal Environmental Science and Technology, demonstrates that algae production consumes more energy, has higher greenhouse gas emissions and uses more water than other biofuel sources, such as switchgrass, canola and corn.

The devil, as they say, is in the details, and the details are far from clear. Using waste water (say sewage treatment plant effluent) may reduce overall water consumption and improve effluent quality. And growing algae in a pond or tank doesn’t coopt farmland that could be used for food crops.

Check the ScienceDaily article for details.

A Greener PVC?

February 8, 2010

It’s not quite alternative energy but making PVC (aka ‘vinyl’, ‘polyvinyl chloride’) plastic more environmentally benign should be big news to anyone interested in greener energy or materials.

Because it’s versatile and inexpensive, PVC is used in a great variety of end uses, from plastic sewer pipe and siding for your house, to shower curtains, blood transfusion bags, and automobile upholstery. PVC, however, has a bad reputation in health / safety / environmental quarters – largely because of phthalate plasticizers, which manufacturers add to the excessively brittle PVC to make it stronger, softer and more flexible.

The problem is that, over time, many conventional plasticizers migrate out of the PVC article and into the environment. Fugitive plasticizers are a big component of that ‘new car smell’ or the unmistakable odor of a new shower curtain – and the major reason environmentalists don’t like PVC.

Now, the Institute of Polymer Science and Technlogy in Madrid has discovered a way to permanently lock-in the plasticizer, by making it an integral part of the PVC polymer molecule. If the discovery proves practical and economic, look for revolutionary changes in large segments of the plastics and chemical industries.

Here’s the citation:
Rodrigo Navarro, Mnica Prez Perrino, Myriam Gmez Tardajos and Helmut Reinecke*
Institute of Polymer Science and Technology (ICTP-CSIC), Juan de la Cierva 3, E-28006 Madrid, Spain
DOI: 10.1021/ma902740t
Publication Date (Web): January 21, 2010

‘Big Rig’ Fuel Savings

February 8, 2010

Back in Nov 09, I wrote about a “boat tail” add-on for tractor-trailer rigs invented by the University of Delft in Holland to dramatically improve fuel mileage for big-rig truckers. Now, Georgia Tech has shown a less obtrusive approach to reducing aerodynamic drag and improving fuel economy.

Georgia Tech's fuel saving big-rig modification

According to the article, “Trucking accounts for 19 percent of our overall fuel consumption … 39 billion gallons of diesel each year. One big reason is drag. At highway speeds, airflow across the square edges on the back of a tractor trailer creates a vortex that works against forward motion. That vortex burns fuel.”

“Georgia Tech estimates their design for reducing that vortex could increase fuel efficiency by about 12%. If applied to the country’s entire 18-wheel trucking fleet, that adds up to savings of 2.4 billion gallons of diesel a year.”

In more familiar terms, that’s a saving of around 160,000 barrels per day – not much more than a drop in the bucket of our 9million BPD foreign oil habit, but significant none the less.

NOTE: Numbers in the article aren’t quite consistent. It appears GaTech is prudently taking credit for only about half the to theoretically possible 12% improvement.