This past Monday, City Council unanimously approved a 5-building research-and-development site after developer HCP (Health Care Property Investors) agreed to commit $1.8 million toward renewable energy generation in the City. $1.5 million will go towards generating either wind or solar power on-site at the R&D campus (with a portion to be spent towards studying wind generation at Sierra Point, much like how the
197-ft. tall wind tower was installed on the Baylands last month). The remainder of the committed amount, $300,000, was negotiated by staff to be a one-time cash contribution, and will be directed for usage off-site (it most likely will be used towards the City Hall solar project, and represent roughly half of the City's cost after a 50% rebate from PG&E is applied).
HCP's development of a 23-acre biotech campus at Shoreline Court and Sierra Point Parkway is the first to abide by the City's Green Building Ordinance, passed in December of last year. Although on-site energy generation is not a requirement made by the ordinance, HCP has acquiesced to the City's environmentally-progressive outlook regarding any new development in town and will be studying whether renewable energy generation through either wind or the sun will be most opportune for the City.
Because discussions to date have centered on a solar installation on top of the proposed parking garage at Sierra Point, as well as on the roof at City Hall, it may be worthwhile to consider what the actual benefits of doing could possibly look like. (Hopefully by this time next year, data from the Baylands wind tower and that which will soon be gathered at Sierra Point will clarify whether or not wind would be an economically feasible source of renewable energy).
Energy from the sun varies from place to place and is very dependent on weather conditions. So, how much would, say, 3 hrs. of sunlight on 1 sq. meter of solar panel actually translate to? If we're talking electricity, and we say that electricity is worth $0.10 per KwH, then 3 hrs. is worth $0.30 KwH. However, the radiant energy conversion rate of PV panels is about 20% or less, so 3 hrs. of sunlight on 1 sq. meter of a solar panel is equal to about $0.06.
How about heat? Well, 1 KwH = 3,400 BTU*, so 3 KwH = 10,200 BTU. Since one gallon of fuel contains approximately 150,000 BTU, then 10,200 BTUs are the equivalent of .07 of fuel oil. Like the radiant energy conversion rate for solar, there is a heat transfer efficiency rate of a solar hot water system. That efficiency rate is about the same as oil burner transfer efficiency - both are between 50%-70%. Now if fuel is selling for $4.00/gal., then the value of 10,200 BTUs is about $0.28 (.07 x 4.00).
Hopefully this sheds some
light on the possible benefit that solar panels can have...but in the meanwhile, you can be assured that careful evaluation will be taking place to determine which renewable energy source is the most suitable for Sierra Point!
* Fuel use is measured in BTUs (British Thermal Units) rather than gallons or therms. You may be interested to know that 1 BTU (British Thermal Unit) is the amount of heat needed to raise the temperature of a pound of water 1 degree Fahrenheit (approximately the heat energy released by striking a match).