Skeptical About New Energy Technology
Here’s an article that begins:
A new type of ultra-efficient engine has been attracting the attention of several big-name investors. The startup EtaGen, founded in 2010, announced recently that it has raised an $83 million Series C round of funding, including from power company AEP, and the venture arms of oil giant Statoil and energy company Centrica. These new strategic investors join EtaGen’s existing investors, Microsoft co-founder Bill Gates and Vinod Khosla’s venture firm Khosla Ventures. The company has now raised $133 million, according to a press release.
EtaGen’s engines aren’t meant to be used in cars (yet), but rather to generate onsite power for companies, buildings and microgrids. EtaGen calls its device a “linear generator,” and it appears to be a new type of free-piston engine that can operate at low temperatures, with high compression and expansion ratios.
I smell a rat.
How excited about this should we be?
First, keep in mind that the efficiency of a combined-cycle gas-fired power plant is about 62%. How efficient can this thing be?
Another red flag: The company is eight years old, has raised Series C funding, and the author says the technology “appears to be a new type of free-piston engine?” Can’t you go see it?
Something’s rotten in Denmark.
Craig is correct.
For the astute and wary wherever you may be – never lose sight of the US Solyndra Solar Company abomination and attack on hard working US taxpayers 10 years ago.
There are many Solyndra look alike’s still popping up everywhere.
Developing a sensitive ‘sniff meter’ is your best defence against these fantasies.
Lawrence Coomber
Not sure about the logic here.
1) Solyndra didn’t work, but most government-backed technologies do.
2) Very few American taxpayers view the government’s backing new technology as an attack against them.
3) Solyndra wasn’t a scam; it was a failure based on an unpredictable fall in the price of conventional silicon panels.
4) The technology discussed here isn’t government-backed.
Outside of these four items, I suppose you have a point.
Craig,
I’m not sure why you are so skeptical.
So far I haven’t seen any requests for government funding or a prospectus seeking funds from mom and pop investors. I’m sure Statoil, Bill Gates and Vinod Khosla etc, are quite capable of investing there own money as they see fit. If they lose, who really cares ?
The technology is hardly new, it’s been around since the 1920’s and example can be found in the refrigeration industry.
I’m not skeptical that it’s a scam; there is nothing theoretically impossible about it. I *do* doubt, however, that there is anything whatsoever to get excited about; I don’t see how that’s possible.
Thermodynamics will win. Always.
For heat engines, there is a hard limit for the maximum efficiency that any heat engine can obtain. That’s the Carnot limit.
Simply expressed, the Carnot limit is (1-(cold temp/hot temp))*100%. Temperatures are degrees Kelvin.
That’s not the efficiency of the heat engine, that’s the maximum theoretically possible efficiency of the heat engine.
So to get to an ideally PERFECT engine of 62% efficiency, assuming the exhaust temp of 300 K, the hot temp would have to be over 790 K, or ~517 C.
That is not going to be obtained in a simple and small unit that someone can purchase to put to power a building. (It’s also worth noting that the smaller the unit, the less close to perfect that it will be. It’s unlikely that small units will get to even 70-80% of the Carnot limit, making 62% efficiency even further off the mark).
But it’s unlikely that they are competing with the super combined cycle turbines. They are competing with personal home diesel generators. Their target is ~35% efficiency.
I suspect that whoever drew up the press release was a third-party press agency with absolutely no familiarity with thermodynamics or engine technology. Then some journalist with equal familiarity with the subject matter (zero) read the press release and interpreted it for us.
Kind of like the child’s game “telephone”, but with supposed professionals doing their jobs poorly.
Nice info, Glenn!