There's a lot of good data to be found in public reports from national labs and other government research papers, but it's not always easy to find or easy to parse.
For years, federal Department of Energy collected and published that information—but it has eliminated that effort under the Trump Administration.
So the Natural Resources Defense Council has stepped into the breach, releasing a new tool to track the reduction in cost and increase in adoption of solar and wind power, electric-vehicle batteries, and LED lightbulbs.
READ MORE: Trump to slash clean-energy funding 72 percent, lauds "beautiful clean coal"
Its report is called Revolution Now, and NRDC also gives viewers access to the full data sets behind the reports, for those who need deeper research.
The nonprofit's reports, in a series of user-friendly charts, show the price of producing wind power has dropped from 6.5 cents per kilowatt-hour in 2008 to less than 2 cents last year.
At the same time, wind-power capacity in the United States has grown from about 25 gigawatts to more than 90 gigawatts.
Photovoltaic solar power field at Volkswagen plant in Chattanooga, Tennessee
The same trend applies to solar power. The cost of utility-scale solar is less than a third what it was in 2008, and installed capacity has grown from almost nothing to more than 24 gigawatts today.
(For "distributed" or "residential" solar, which includes businesses, costs have fallen by half, and capacity has reached another 16 gigawatts.)
Electric vehicle battery packs show a similar trend, with prices dropping from about $1,000 per kwh to a little over $200 per kwh, while sales of plug-in vehicles have reached more than 3/4 million.
READ THIS: Lithium-ion battery packs now $209 per kwh, will fall to $100 by 2025
The Trump Administration has made it clear that its priorities include neither keeping track of nor promoting renewable energy.
The President's most recent budget proposal would have canceled funding for the Advanced Research Projects Agency for Energy (ARPA-E) and loans from the Advanced Technology Vehicles Manufacturing program.
It would also have slashed 72 percent from the budget of the DOE's office of Energy Efficiency and Renewable Energy, but Congress restored much of the funding for all of those efforts in the recent budget bill.
Wind farm outside Fort MacLeod, Alberta, Canada [photographer: Joel Bennett]
With those priorities, it's helpful to have non-profit organizations such as the NRDC to fill in the gap, and their efforts will no doubt be appreciated.
Since the numbers come from the government, we don't doubt their veracity.
Unfortunately, they may have less impact in a report published by an environmental lobbying group than they did in a similar—if less user-friendly—report from the government itself.