On Tuesday, Google announced in its official blog that it invested another $94 million in a portfolio of four solar photovoltaic (solar cell) projects. These are being undertaken by Recurrent Energy near Sacramento, California. The investment brings Google's portfolio of clean energy investments to $915 million, nearing the $1 billion mark. By the end of 2011, Google will have helped fund 10,000 homeowners set up solar PV panels on their rooftops. Google is investing alongside global investment firm KKR and Recurrent Energy, a leading solar developer. The energy produced by these projects is already contracted for 20 years with the Sacramento Municipal Utility District (SMUD), and is governed by a feed-in tariff program (FIT), which adjusts homeowners' utility bills by balancing how much their PV panels feed into the grid, and how much the homeowners draw from it.