Welcome to Solar in California

On April 12/11 Governor Brown of California signed legislation requiring the State’s utility companies to provide a minimum of 33% of all energy provided in California to be from renewable sources by 2020.  In 2009 the portion of the total from renewable sources was almost 21%.

Like so many government programs, the problem is that no one seems to have looked into how this dream might be accomplished. The idea, whether ill-conceived or just political, was that if the government said you had to do it, you had to do it.  There was no plan for how to implement the program.   The requirement was that the utility companies had to provide it, but no provision was made for how to produce it.

A likely candidate for providing a substantial portion of this renewable energy is solar energy.  The Sun produces enough energy each second to supply the earths needs for a million years.  Only a tiny amount of that actually strikes the Earth, but even that resource is enormous.  The question that arises is where to locate the millions of panels necessary to harvest this vast resource.  There are two choices, systems mounted somehow on buildings, or systems mounted somehow on the land.

One suggestion is to build the arrays into new construction, but new construction usually also adds new demand.  So for new construction to contribute to the additional renewable energy required by the law, a building will have to provide not only 100% of it’s own energy, but even more to contribute to the current shortfall.  It is unlikely for new construction to be able to do that.  Any building 3 stories or more has very little roof space to offer because much of it is already taken up by heating/cooling units, ventilation access, and other rooftop appendages.  There are techniques that can apply solar panels to the exterior of buildings, but many are expensive, and some are experimental or under development.

Large warehouses are an excellent place to put the arrays.  They use less energy than buildings filled with offices full of busy people, and they offer large rooftops.  The rooftop space available for an array is about equal to the floor space inside the building. High rise office buildings in the other hand, offer very small rooftop space when compared to the internal floor space, and offices full of busy people consume much larger amounts of energy than warehouses do.

Parking lots offer a substantial amount of sun drenched land that could be used to collect the energy, but it’s expensive to build the structures to hold the arrays.  In effect, we will have to build roofs, like carports, over all the parking stalls.  That is a great idea since the rooftops would keep the cars cooler, and the amount of gasoline required to cool them after sitting in the sun would be less.  But they are expensive to build.

So, the most likely place to put these solar arrays would be on the land.  And that is quite an attractive place for them.  But there are problem in trying to find suitable land to use.  Most people don’t want to live next door to an array, so we will want to keep them out of sight.  The desert is the place most people think about for solar systems, but the desert is largely unavailable due to environmental considerations.  They are home to many endangered and protected species.  So it falls to the farms and the hills to provide the locations necessary to host the arrays.  More about land based arrays in a future post.