The big climate news in advance of next week’s U.N. climate summit is a new global commission report that finds the investments needed to avert a climate crisis would likely not result in any net cost.

According to the New York Times, “an ambitious series of measures to limit emissions would cost $4 trillion or so over the next 15 years” but that’s only “an increase of roughly 5 percent over the amount that would likely be spent anyway on new power plants, transit systems and other infrastructure.”

More importantly: “When the secondary benefits of greener policies — like lower fuel costs, fewer premature deaths from air pollution and reduced medical bills — are taken into account, the changes might wind up saving money…”

Shocking? Well, only if you haven’t been paying attention.

Back in 2009, when the Democratic-run House passed legislation to cap carbon, the nonpartisan Congressional Budget Office found it would trim the budget deficit over 10 years, and impose only negligible costs to the average household, with low-income households making money.

Capping carbon simply is not a budget buster.

It is, however, a cost-shifter, making fossil fuels more expensive while making clean energy more affordable. Where the politics of climate gets complicated is in trying to craft a plan that would make the cost shift gradual enough so affected industries can more easily adapt.

But another political complication in forging a global agreement is determining how much aid should wealthy developed countries — which have for decades spewed untold amounts of carbon into the atmosphere — should give to developing countries which are otherwise tempted to invest in cheap fossil fuels to grow their economies.

The global commission’s full report makes clear that aid to poorer countries, in the form of grants and concessional loans, will still be needed. But hopefully the understanding that clean energy investments pay for themselves over time will make those numbers easier to crunch, and make it easier for the international community to strike a deal by the end of 2015, when the nations of the world will convene in Paris.