A potential answer to California’s severe water shortages is groundwater banking, which involves creating incentives for municipalities, farmers, and other water users to percolate water down into sub-surface aquifers for later use.
Blessed with lots of sun and keen to cut its reliance on imported oil, Hawaii has moved to the forefront of residential solar installations in the U.S. But financial and technical hurdles are slowing the state’s drive to generate 40 percent of its electricity from renewable energy by 2030.
While it has environmental advantages over other forms of ethanol, cellulosic ethanol has proven difficult to produce at commercial scale. Even as new production facilities come online in the U.S., a variety of economic and market realities suggest the new fuel still has big challenges to overcome.