In the social networking world, LinkedIn just went public and Groupon and Facebook look to float on public bourses at multi-billion dollar valuations in the near future.

What about greentech companies that actually make useful products?

Well, Kior, a biofuel firm, went public last week. BrightSource Energy, the solar thermal firm, filed its S-1 a few months ago, and Enphase Energy, the PV microinverter firm, filed its S-1 earlier this month.

Add another greentech company to the IPO aspirant list -- Aspen Aerogels just filed its IPO registration papers with the SEC. The energy efficiency company designs, develops and manufactures high-performance aerogel insulation.

BASF and others put $21.5 million into the New England-based Aspen Aerogels company last year. This week, regulatory filings showed that it raised another $30 million.

As Michael Kanellos has written, aerogel has been the world’s best form of insulation for nearly 100 years. The material, however, has only occupied niche markets because of its expensive price.

Aerogels look like hunks of plastic but are actually complex, porous strands of silica that capture air or molecules. The high cost of aerogels comes largely because the raw materials get cooked in high temperature/high pressure environments in relatively small batches.

From the Aspen Aerogels S-1:

  • Our technologically advanced products are targeted at the estimated $32 billion annual global market for insulation materials. Our insulation is principally used by industrial companies, such as ExxonMobil and NextEra Energy, that operate petrochemical, refinery, industrial and power generation facilities. We are also working with BASF Construction Chemicals and other leading companies to develop and commercialize products for applications in the building and construction market.
  • We achieved a compound annual revenue growth rate of 46.7% from 2008 to 2010, with revenue reaching $43.2 million in 2010.
  • Our aerogels are complex structures in which 97% of the volume consists of air trapped in nanopores between intertwined clusters of amorphous silica solids. These extremely low density solids provide superior insulating properties. Although aerogels are usually fragile materials, we have developed innovative and proprietary manufacturing processes that enable us to produce industrially robust aerogel insulation cost-effectively and at commercial scale.

The company had sales of $12.2 million in the first quarter of this year with net losses of $1.7 million.

Although the company sizes the market at $32 billion, the market for insulation is fragmented and diverse. The primary markets for insulation are: industrial, including use as covering for pipes, valves andstoragetanks; building and construction, in walls, floors and ceilings; and original equipment manufacture, including use in transportation, appliances and apparel applications. Aspen appears to be addressing the industrial market first.

A fragmented market with multiple sales channels is difficult to address for a small company. In any case, it will be interesting to see how public markets appraise the future of a pure-play energy efficiency company.