The cost, $1.5 trillion, $400 billion less than the current COVID rescue plan. 

COVID was of course something we had never seen on this scale before, but this is an important point-- for all the time we're told the time/resources aren't there for clean energy action, when there was massive crisis with lives on the line, we found the money and the ability to push this through. Shows that the climate crisis needs to be treated in the same way if we're to get the scale of mobilization that's truly necessary. 

It may be considerably less than that, An NREL analysis from 2018 showed that the US could 30% of its electricity demand from 14% of roofs with 16% efficient modules. Now that 20% efficient modules are common and 24% will be available from about 2024, it may well be that combined with European levels of building and process efficiency rooftop solar could be supplying 35% of demand.

The key is to accept curtailment instead of transmission. The US has far lower population density than Germany and by 2025 Germany is on track to produce 70% of its electricity demand from RE which would translate to about 1,100 MWh/Square km. Even in a densely populated area such as New York state, 1,100 MWh/square km would supply all electrical demand. By 2030 with widespread adoption of rooftop solar, energy efficiency and offshore wind NY could have an annual capacity of  1,500 MWh per square km. Some of that would be stored but some curtailed meaning that little if any new transmission would be needed

"According to Bill Gates and Breakthrough Energy Sciences (BES), the country can achieve 70% carbon-free electricity and emission reductions by 42% by 2030."

Actually, Bill Gates never made that statement, or agreed with it. Breakthrough Energy Sciences is an umbrella organization founded by Gates in 2015 with an (paltry, for Gates) initial investment of $2 billion. At the time he said

"The renewable technologies we have today, like wind and solar, have made a lot of progress and could be one path to a zero-carbon energy future...but given the scale of the challenge, we need to be exploring many different paths."

Since then Jeff Bezos, Michael Bloomberg, Richard Branson, George Soros, Tom Steyer, and other venture capitalists have jumped on board. With no particular interest in solving climate change, they nonetheless recognized the mythical 'energy transition' is a pot of gold, and have enlisted an army of inexperienced, twenty-something dreamers to help them in their quest.

And since then, Gates has apparently changed his mind about renewables. In 2019 he called the idea of powering a modern industrial economy with them "so disappointing," adding

"Whenever we came up with this term of 'clean energy', I think it screwed up people's minds, 'cause now they don't understand [what it would require]...

"I was at this conference in New York, and all these financial guys got on stage and said,  ''we're going to rate companies in terms of their CO2 output, and the financial markets are magical, and all of a sudden the CO2 will stop being emitted."

"And I was like, 'OK, how are you going to make steel? Do you guys on Wall Street have something in your desks that makes steel? Where's the fertilizer, plastic, cement, where's it going to come from? Do planes fly through the sky because of some number you put on a spreadsheet?'

"The madness of this so-callerd 'finance is the solution'...I just don't get that. There is no substite for how the industrial economy runs today."

https://www.youtube.com/watch?v=9xe3BWPsBTU