Nobody said it would be easy. Gov. Charlie Baker is in the midst of a multi-step process to keep electricity affordable while using more renewable energy.

Promoting renewability to achieve affordability requires something Baker calls a "combo platter" of different energy sources. That means mixing and matching from options in columns A, B, and C to obtain the greenest electricity at prices that won't shock consumers.

"By being able to procure large quantities of clean energy including hydro energy, solar, wind and offshore wind, we're able to meet our emissions reductions goals and achieve cost effective energy for consumers," Judith Judson, Baker's Commissioner of the Department of Energy Resources told WGBH News.

To achieve that balance, Democrats in the legislature flashed the governor a green light under a 2016 law outlining the state's clean energy goals and how to achieve them. Since then, Baker has been beavering away to combine relatively inexpensive Canadian hydropower with somewhat pricer sources like solar from other states or onshore wind.

And then there is biomass - the burning of wood to produce energy.

"Burning biomass is not carbon neutral, it actually emits more CO2 than burning fossil fuels," Mary S. Booth from the Partnership for Policy Integrity told WGBH News.

"To give subsidies to increase wood burning in the state really doesn't make sense from either a climate or an air quality perspective," Booth said.

Judson said her department is still evaluating several new sources of energy, including biomass, as part of regulations to be issued later this year. Wood burning, she said, would not be a part of the major clean energy contracts currently under scrutiny by the administration.

If Booth's point of view prevails in the longterm, Baker and his team of energy managers will need to adjust the state's planning toward reliably clean sources.

Baker has until January 25 to choose a contractor to transmit power. That decision will affect Baker's ultimate combo, but, per the law, over half the energy will come from offshore wind projects still being built.