Saturday, May 8, 2010

Is the San Luis Valley Ready for a Microgrid?

As communities and utility companies battle over power lines and who is to blame for falling behind on renewable energy goals, a quiet revolution has occurred right under our nose.

With little fanfare, the San Luis Valley has already become the best model for distributed renewable energy generation in the West and maybe even the Nation.

When the first energy crisis shook the country in the 1970's, solar energy aficionados and off-gridders flocked to the San Luis Valley where cheap land, loose zoning and cool sunny skies offered endless opportunity. A myriad of passive and active solar powered, off-grid homesteads cropped up around this off the beaten track, rural agricultural valley.

We'll feature some of these projects in future blogs.

Over time, solar experiments grew bigger and bolder.  When the 8.22 MW SunEdison plant went online in April of 2007, the San Luis Valley was briefly home to the largest solar PV farm in the US.  But it didn't stop there.

Online & permitted solar PV:
  • SunEdison, 8.2 MW on 80 acres, Mosca
  • Alamosa High School/SunEdison, 600kW (.6 MW) on 5 acres, Alamosa
  • SLV Solar Irrigators, 6 - 10 kW PV systems (60 kW), various
  • SunPower/Greater Sand Hill Solar, 17 MW on 200 acres,
  • Lincoln Renewables, 37.4 MW, unknown acreage, Alamosa
We're fast approaching 100% solar generation of our average base load electricity demand (50-65 MW) during daylight hours.

What we already have is three high-voltage transmission lines.  If upgraded, these existing lines could carry up to 575 MW of green, clean energy to distant cities (see alternatives).  Shouldn't we make the most of what is here now before spending untold millions on another transmission line?

According to energy experts, the San Luis Valley is doing everything right and is well positioned to be a grid-supported energy independent region, perhaps even the first Microgrid in the nation.


WHAT IS A MICROGRID & HOW DOES IT WORK?

"Energy would come from a mixture of renewable energy sources, microturbines, fuel cells, and interconnection to the existing utility grid. Converters in secondary distribution frames would isolate short circuit currents. Since the utility grid is a secondary source, the microgrid would be protected against the grid's surges and failures. The savings would be generous. Microgrids could "sell" excess power to the utility grid. Costs decrease because of reduced energy storage, less down time, equipment operating at maximum efficiency, lower hardware expense, and optimal power input control based on energy costs." 

We'll post more on this but for a quick overview see Science News:  Better than Power Grid: New Microgrid Network