Despite high-profile support from President Barack Obama, US funding for low-carbon energy research has stalled in Congress — but current technologies like wind and solar power keep plugging away.

The White House requested $7.7 billion in R&D funding for 2017, spread across a dozen federal agencies, as part of an international "Mission Innovation" project to expand the use of low-carbon energy. But the Republican-controlled appropriations committees in the House of Representatives and Senate have already been hacking away at that amount, shifting money away from studying new energy sources and extending the reach of renewable power.

"These technologies have been the No. 1 technology priority for this administration," said Matt Hourihan, the head of the R&D Budget and Policy Program at the American Association for the Advancement of Science. But Obama "has never really gotten anywhere near what it has proposed, at least on the efficiency and renewable energy front," Hourihan said.

"We've become accustomed to seeing major proposed increases for all of them in the president's budget requests over the years," he said. "But in a Republican Congress, it's not a funding environment that's conducive to big increases for most of these activities."

'There's a lot of affordable clean energy available to deploy right now.'

There have been no big increases in low-carbon energy research since 2010, Hourihan said. Instead, House and Senate budget bills have shifted money into nuclear power and fossil fuel research, adding more than $400 million to those programs and cutting spending on others.

"The Senate has flat-funded renewables. The House has proposed some pretty deep cuts — over 10 percent cuts — for the renewable energy and efficiency office," Hourihan said. The major exception is the Department of Energy's Advanced Research Projects Agency-Energy, which would get a fraction of a percent more money in the Senate bill and a 5 percent boost from the House; President Barack Obama had asked for a 20 percent boost, to $350 million.

But clean-energy advocates say current technologies are chugging along despite the hurdles to research.

The progress has been buoyed by tax credits for wind and solar power that Congress extended in a December budget deal. The United States added enough solar and wind power in 2015 to light about 3.8 million homes, according to the US Energy Information Administration (EIA) and industry estimates. And federal regulators just approved a new long-distance power line that will carry electricity from wind farms in Texas and Oklahoma to the Southeast.

The price of renewables is still higher than coal or comparatively cleaner natural gas, but the gap is shrinking as more wind and solar capacity comes online, said Larry Chretien, executive director of the Energy Consumers Alliance of New England.

"There's a lot of affordable clean energy available to deploy right now, and costs are going down while quality is going up," Chretien said.

Power sources that don't put out planet-warming carbon dioxide produced a third of American electricity in 2015, according to the EIA. Most of that came from nuclear power, which despite its light carbon footprint remains politically controversial and economically challenged.

But dams, wind turbines, biofuels, and solar panels made up 13 percent of US generation last year, and non-hydroelectric renewables now make up more than half of that wattage, the EIA reported. Wind power capacity has grown more than sevenfold in the past decade, while solar capacity is more than 50 times higher than in 2005.

Worldwide, investors poured $286 billion into renewables in 2015 — six times more than in 2004, according to the UN Environment Program. Wind and solar installations made up nearly $200 billion of that: China's massive push for renewable power has driven down the prices of solar panels worldwide, and more than half the world's added electric power capacity came from renewable sources last year, the agency reported in March.

But about $9 billion went into new research, including $4.7 billion in corporate investments. A new private push called the Breakthrough Energy Initiative is hoping to add to that, calling for a moon shot-like drive to produce zero-carbon power. It's backed by a deep bench of billionaires like swashbuckling media and airline tycoon Richard Branson, hedge-fund chieftain George Soros and Microsoft co-founder Bill Gates, who has pledged $2 billion for the project.

Jonah Goldman, a spokesman for Gates, says the first investments from that $2 billion are expected to be funded by the beginning of 2017. But in the process, Gates has rankled potential allies by seeming to slight the rapid growth of existing renewables, urging more research to produce an energy "miracle" and dismissing the prospect of a carbon tax, which is designed to make fossil fuels more expensive to burn.

Chretien said that putting more money into R&D is a good idea, it shouldn't be an either-or proposition: The world "just can't wait" for some over-the-horizon miracle.

"If we wait five more years or 10 more years or 20 more years for the miracle he's talking about, that's just putting more greenhouse gases into the atmosphere," he said. But producing more solar and wind power "doesn't require a miracle. We can do that today."

Goldman said Gates has spoken "on a number of occasions" about the importance of extending current technology while funding new R&D.

"His focus is on the latter, since we have dramatically underinvested in the research side of the equation for far too long," Goldman told VICE News via e-mail, adding, "It's unfortunate that people see this as an either/or."

"We are committing a fair amount to the deployment drivers through tax credits and renewable fuel standards, but doing nearly nothing when it comes to the innovation side," he said. "Bill is focused on seeing that side come more into balance."

Follow Matt Smith on Twitter: @mattsmithatl