jj906x1Public demand response company EnerNOC has filed to sell an additional 3.75 million shares of common stock — including shares currently owned by investor Foundation Capital, which is attempting to dial down its ownership. The Boston-based company says it plans to use the money raised as working capital.

Right now, the firm owns about 14 percent of the company, according to VentureWire. After the sale, it will only own 9.4 percent. About 660,000 of the shares for sale will come out of Foundation’s stake. The company is also offering 3 million new shares, and 90,000 owned by its chief executive, Tim Healy. Some of the money brought in may also go toward EnerNOC’s acquisition strategy, as well as expansion of operations inside and outside the U.S.

Foundation Capital had been the lead investor in EnerNOC’s second round of funding in 2005, leading the $7.75 million raised with $5 million. The company went public in 2007 at $26 per share. Today, it hovers at $28.27.

It recently reported revenue of $42.3 million in the second quarter of 2009, beating analyst expectations of $39.1 million, and up 78.5 percent from the second quarter last year. It is projecting between $88 and $98 million in revenue for the third quarter.

EnerNOC is one of the leading players in the demand response space. The company is hired by utilities to make power-saving deals with large commercial companies. When demand for electricity approaches supply, utilities are at high risk for brownouts, outages and other damage to the grid, raising maintenance costs and challenging service quality. When demand starts reaching problematic levels, utilities can call EnerNOC, which in turn puts calls out to major energy users like retail stores, etc. to immediately reduce their electricity usage. These companies are then compensated by the utility for the energy they didn’t use, and the utility averts a potential crisis — making it a win-win on both sides, EnerNOC says.

EnerNOC competes with the likes of Comverge and CPower, but has had several big wins give them an edge recently. Not only did it land $100 million worth of energy capacity via electricity transmission organization PJM Internconnection in May, it has also branched into carbon management with the June acquisition of eQuilibirum Solutions.