John Mott-Smith [Credit: Davis Enterprise
This column by John Mott-Smith, a member of Cool Davis Initiative, is regularly published in the Davis Enterprise and is cross-posted here.

How are we doing?

Environment California recently released a report on the state of photovoltaic solar energy systems in California cities. The report included some surprises and some points of local interest.

They looked at “distributed solar” systems installed on rooftops of homes and businesses by owners or third-party financing companies; utility scale solar systems were not included. The results of the survey are expressed in multiple ways in order to account for differences in size between, say, the cities of Davis and Los Angeles.

The first surprise (at least for me) was that Los Angeles, despite being by far the largest city in the state, did not have the highest number of installations nor are they producing the most solar power. San Diego takes both these honors with 4,507 solar installations producing almost 40 megawatts (40 million watts) of solar power, which would rank it among the top 25 nations in the world, with more solar power than the entire country of Mexico.

The city of Davis, small as we are, comes in No. 16 in the state with more than 700 installations.

When looking at the number of installations in different-sized cities, Davis is ranked No. 4 in the state for “mid-sized” cities (bigger than “towns” but smaller than cities like Sacramento). Ahead of us are Santa Cruz, Clovis and Rocklin.

The city of Davis, small as we are, comes in No. 16 in the state with more than 700 installations.

According to the report, Davis has solar installations on a little more than 1 percent of our homes and businesses. As noted above, this does not count solar hot water systems, a large number of which have been installed to heat swimming pools and spas.

Looking at the data another way brings forward another set of champions. The city of Woodland came in second in the state among mid-sized cities in the number of watts of photovoltaic electricity produced per resident (100), trailing only Chico (110).

Davis came in 30th, with slightly less than half of Woodland’s total. Davis has more installations but systems in Woodland are larger on average.

Our neighbor to the west — Sonoma — seems to be the pace-setter. It comes in first for “large towns” (population between 10,000 and 50,000) with 4.5 installations per 100 residents. Sonoma also is first in its category with 507 watts of installed capacity per person.

Interestingly, Sonoma is one of the few jurisdictions in the state implementing the Property Assessed Clean Energy (PACE) program that allows homeowners and businesses to install solar energy systems without any upfront cost and then use energy savings to pay back the installation cost through an assessment on their property tax bill (see THE BIG DAY below).

There may be some questionable assumptions or data in the report that skews the rankings, but overall it looks like Davis and Woodland are doing pretty well.

THE FOREST AND THE TREES: One of the factors limiting Davis residents in terms of solar installations is our tree canopy. Most homes and businesses benefit from the cooling effect of shade trees. We have an outstanding urban forest. In many cases, it’s not possible to have both shade trees and solar systems on the same piece of property. In fact, by most estimates, about half the homes in Davis don’t have enough sun to justify installing a solar system.

More than a few people have asked why we can’t build a “solar farm” somewhere outside town that residents could buy into; effectively owning solar panels that produce electricity, the amount of which is subtracted from their home or business energy bill. Good question, and one the city is working on answering.

You might not think such a thing would require legislation, but it does. Our local hero, city of Davis Sustainability Director Mitch Sears, is working with stalwart state Sen. Lois Wolk to enact a law to enable Davis residents to do just that and facilitate efforts to accomplish the city’s goal of obtaining 100 percent of its electrical energy from renewable sources.

THE BIG DAY: Birders sometimes set aside a specific day to go out en masse to try to see as many birds and bird species as possible. A “big day” in the energy world is of a different sort, but one took place on Jan. 23.

The Davis Natural Resources Commission had three energy-related items on its agenda. One was the expansion of the PVUSA site north of Davis to accommodate a “solar farm” as described above. The second was a program to aggregate local government employees into a bulk purchasing program for solar energy systems that substantially reduces the cost of installing rooftop solar (with the potential to expand this opportunity to all Davis residents).

The third was participation in a countywide PACE program for commercial properties, including apartment buildings with five or more units.

Although there were questions about each of the “trees,” the commissioners kept their collective eye on the “forest” by acting positively on all three.

The wheels of change at times turn painstakingly slow, but the city of Davis continues to push forward with its energy policy and maintain its leadership position in efforts to reduce greenhouse gases.