Biofuels appear to be losing their appeal with investors.

Kior, a company that claims it can make a synthetic version of petroleum out of wood and farm waste, sold 10 million shares of stock in an IPO yesterday for $15 a share, lower than the $19 to $21 price it had earlier anticipated.

And today, on the first day of trading, the stock is snoozing at $15.02.

The relatively uneventful IPO can in part be chalked up to the fact that Kior, like other biofuel startups going public, is not profitable and is not yet in commercial production. Kior lost $45.9 million in fiscal 2010.

Add on top of that the recent events in Washington. The U.S. Senate last week voted 72 to 37 to eliminate the 45-cent-per-gallon tax credit on biofuel and the 54-cent-per-gallon tariff on imported ethanol. The Senate action isn't law, but it has received support from both conservative tax groups and environmental organizations. The G-20 is also asking Washington to eliminate biofuel support. Yes, ironies abound. Some conservative groups have opposed eliminating tax credits for fossil fuel companies, despite recent record profits, and the G-20 has rarely met an agricultural price support policy it doesn't like, but such is life.

Biofuel and biochem companies have enjoyed a mini-boomlet until now. Gevo, which makes a renewable form of isobutanol, went public at $15 a share in February and soon rose to $26 a share. Gevo CEO Patrick Gruber told us two months ago that the company planned on expanding production to 350 million gallons by 2015. Gevo just broke ground on an 18-million-gallon facility.

The stock, however, is now back at $15.

Solazyme, which produces chemicals, food additives and fuel from algae, held its IPO in May, selling its shares at $18 each. (Earlier, it had anticipated getting $15 to $17.) The price went up to nearly $21 on the first day of trading, but now hovers at around $20.

Codexis went public at $11 last year and now trades at $9.

Only Amyris, which has a microbe that can convert farm and wood waste into a hydrocarbon called biofene that can be used as an ingredient in a number of substances, has seemingly defied gravity. It went public at $17 last year and is selling for around $29.