'Diversity is a Key' 

Editor:

Greg King is right that our focus in achieving energy sustainability should be on reducing our overall use ("Why Deindustrialization (Not Wind) is the Answer," April 25). But his insistence on a monoculture of rooftop solar only as the supply side solution makes no sense. Mr. King has an illustrious career in protecting our North Coast forests and notes correctly in his article that loss of global biodiversity, like that found in those forests, is a threat on par with climate change. So he should understand that just as diversity is a key strength in ecosystems, human society and agriculture, it is also essential to a resilient energy economy.

California state policy recognizes a number of energy sources as renewable, including solar photovoltaics, solar thermal, wind, geothermal, small hydro, biomass from forest and agricultural waste, and biogas derived from landfills, wastewater plants, dairy farms and food waste digesters. Each of the technologies for capturing these energy sources has benefits and shortcomings. A diversified portfolio combining them will allow us to have reliable, round-the-clock energy in a 100-percent renewable future that is not far off. Aside from rooftop solar, which certainly can play an important role in this diverse mix, most of these resources cannot feasibly be captured with individual household systems. Hence the need for some of our energy to come from larger, centralized generation facilities. Another concern with over-reliance on rooftop solar is cost. Data from the National Renewable Energy Laboratory and other sources show that watt for watt, rooftop solar is more expensive than centralized renewable energy projects. In this era of skyrocketing electric rates, we cannot ignore that fact.

Rooftop solar is a fantastic technology, but it is not the only strategy we should look to in achieving a reliable and affordable clean energy future.

Richard Engel, Arcata