23 Aug Webberville Solar Farm

Austin's first solar farm opened earlier this year, and since it's open to visitors, I had to check it out. The 35-megawatt Webberville Solar Farm is way out east of town, on a 380-acre parcel near a substation (which kept to a minimum the transmission infrastructure that needed to be built to accommodate all of the new generation).

Austin Energy is committed to purchasing the energy generated at the site — expected to be over 50,000 megawatt-hours each year — for the next 25 years, as part of its goal of 30% renewable energy. Solar power is optimal for a location like Texas, where there is ample sun, especially at times of peak demand. It's no secret that we need more generation capacity, and it doesn't make sense to spend $400 million to build a traditional power plant whose power will only be needed for a few hours on the hottest summer afternoons; solar farms (and rooftop photovoltaic systems) are ideal because they happen to generate most of their power during the times we need it most.

But back to the stars of the show:

Apologies that the photos aren't coming through properly.  To see the original post with pictures, go to http://www.greenhousegoodlife.com/2012/07/35-megawatts.html.

The panels are mounted on frames that allow them to pivot to follow the sun throughout the day. Every few minutes, a creaking sound indicated that a bunch of panels were pivoting a degree or two. The farm has this great observation deck for viewing the site:

From the observation deck, you can see the white structures that house the inverters (devices that convert the power being generated by the panels from direct current (DC) to alternating current (AC). Unlike inverters used with rooftop solar, which are roughly the size of the main electric panel, or microinverters, which are the size of a car stereo, these massive inverters serve hundreds of panels each.

Solar power is low-maintenance compared with traditional forms of energy, but there are two maintenance issues at this farm. The first, which is an issue for any solar array, involves cleaning the panels. Staff has just finished the process of cleaning all of the panels for the first time (after nearly a year in service) and anticipate needing to clean them one to four times per year in the future.

The second issue is more site-specific: weeds.

When the rows and rows of panels were constructed in the midst of last summer's drought, weeds weren't an issue, but with this year's rains, some of them have grown tall enough to begin to block the bottoms of the panels, potentially compromising solar production. Management is exploring the possibility of bringing in a flock of sheep to keep the weeds down.

For additional information or to visit the site, which is open to the public Tuesday mornings and Thursday afternoons, go to the Webberville Solar Farm website.

For more by Devon Bijansky, including a chronicle of the process of designing and building a five-star green home in Austin, check out her blog, Green House, Good Life.