UPDATE: Our solar power monitoring station is offline. We collected
two years of data, but we finally had to clean out our computer corner.
It was hard to tell the cobwebs from the data wires, so we had to take
our rig apart.
What did we learn? We learned that you can produce solar power in
Port Angeles. Sequim may boast about being in the rain shadow of the
Olympic Mountains, but Port Angeles is spared much of the rain and
cloud as well. We also learned that the Bonneville Power Authority can
produce hydro-electric power much more cheaply than we can produce
solar power. Our break even time would be nearly 30 years.
We will leave this part of our site online for a while longer.
Perhaps someone might find our data or methodology useful. It was fun
while it lasted, but it appears that Kaleberg Solar Symbionts has
passed on.
We were interested in installing solar electric power, but according to the solar energy maps the northwest was the worst possible place to do so. These maps, it turns out, were based on actual pyranometer based measurements in Seattle, Quillayute and a few other stations within a hundred miles of us in Port Angeles. None of these maps seemed to take the Olympic Mountains' rainshadow into account.
So, we decided to try measuring our available solar energy ourselves. The right way to do so was using a pyranometer, but pyranometers cost nearly $1000. This was way more than we wanted to spend.
Instead, we built ourselves a little solar power measurement system. The measurement component consists of a pair of little solar cells, rated 3 volts DC and 20 milliamps each. At best they produce a total of 120 milliwatts, but they should provide an honest model of what a larger solar array would produce. After all, they are made of the same silicon.
All we had to do was measure the voltage (electric energy) and the amperage (electric current) to compute the wattage (electric power) we could obtain. Since voltage and amperage can get intertwined in poorly designed circuits, like the ones we make, we used one cell to measure voltage and one to measure amperage.
We bought the solar cells and a bunch of other stuff from Radio Shack, including the components of a little operational amplifier to turn the current into a voltage which is what we could measure. We hooked these up to a Vernier LabPro Interface which is in turn connected to one of our proliferating Macintosh Powerbooks via a USB interface. The analysis software that updates these pages is written in Real Basic, a truly convenient programming language in these software dark ages.
We are sure that anyone with any knowledge of solar power engineering or circuit design will be suitably shocked and appalled at our approach, but it should provide us with some empirical sense of insolation and solar energy potential in the rainshadow region of the Northern Olympic Peninsula.
This project started in the fall of 2001, so there is only a little data collected.
If you would like to see what these solar power estimation tools say about your location, try out PVWATTS.
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