A White House initiative to boost investment in clean energy and climate change projects has spurred more than $4 billion in commitments from private investors, foundations and philanthropies. The funding doubles the funding goal set by the Obama administration in February, officials said.

“The response over only a couple of months has exceeded even our ambitious expectations,” Brian Deese, a White House senior adviser, told reporters on a conference call.

Investments will help drive improvements and lower costs in clean-energy technologies such as solar photovoltaics, wind power, advanced batteries, energy-efficient lighting and fuel cell systems for vehicles and energy storage, the White House said. While the costs of solar and wind energy systems have plunged dramatically in the past few years, renewables still compose only a small chunk of total U.S. energy production -- roughly 11 percent, including biofuels and hydropower, the U.S. Energy Information Administration estimated for 2012.

The largest commitments under the White House initiative include $500 million from the University of California and $500 million from Goldman Sachs. The New Zealand Superannuation Fund, a sovereign wealth fund, committed $350 million to clean-energy projects, while the Alaska Permanent Fund pledged $200 million and TIAA-CREF, a New York financial services organization, committed $100 million.

Those dollars come on top of the $7.6 billion in federal clean-energy funds that President Barack Obama requested in his 2016 budget proposal. Earlier this month, scientists and economists from around the world proposed a $150 billion, 10-year research program to make renewable energy cheaper than coal-fired power.

The Obama administration on Tuesday also announced a series of executive actions to encourage private sector investment in alternative energy technologies. Through its new Clean Energy Impact Investment Center, the Department of Energy aims to make it easier and cheaper for investors to support projects to reduce greenhouse gas emissions and fight climate change. The actions will reduce transaction costs, clarify relevant investment rules, improve financing options and offer greater transparency in federal funding of clean-energy research and development programs, the White House said.

“The idea is to make the department's resources … including, of course, our 17 national laboratories … more readily available to the public, including the mission-driven investors,” Energy Secretary Ernest Moniz told journalists on the call.