by Ceal Smith
Tessera Solar released its plans to construct a 200 Megawatt (MW) solar power plant on approximately 1,525-acres of private land southeast of the Town of Saguache.  This proposal marks the first industrial solar development permit application to be considered at the county level in the San Luis Valley.  As such, how Saguache County handles this project will set an important precedent.
Regulation of industrial solar development has been the topic of rigorous debate among the Saguache County Planning Commissions, the Board of County Commissioners (BOCC) and concerned citizens for the past year.  This spring the BOCC voted to apply the existing 1041 Land Use Regulations.  The Commissioners did agree to use the draft Solar Facility Regulations as guidelines for permitting solar developments.
The Tessera project will be the topic of Tessera Permitting Director Richard Knox’s presentation at the SLV Energy Fair in Crestone on Sunday, Aug. 30th and a public open house in Saguache on Aug. 31st.
Although it’s the first to come before the BOCC for approval, the Tessera Project is not the only industrial-scale solar development proposal in Saguache County.  Last year the Bureau of Land Management conducted an extensive review of a 150 MW OptiSolar plant proposal on 2,100-acres of public lands northeast of the Town of Saguache.  The BLM approved the OptiSolar application but because it’s on public land, it must now go through an Environmental Impact Study (EIS) as required under the National Environmental Policy Act
(NEPA).  An EIS normally takes 1-2 years to complete; however, Interior Department Secretary Salazar has made expediting renewable energy development on public lands a priority.   The OptiSolar site is one of four solar energy zones, comprising a total of 22,380-acres of public land being considered for withdrawal for industrial solar development in the San Luis Valley.  The BLM is taking public comment on the Solar Study Areas through September 14, 2009 (see:
Renewable Energy Systems Americas (RES) also announced plans earlier this year for a 200 MW Concentrating Solar Power (CSP) project on more than 2,500-acres on the Meadow Ranch near the Town of Center in southern Saguache County.   While RES presented its preliminary application to the County Land Use Department in March, a formal permit application has yet to be filed.
While opinions about the desirability, impacts, costs and benefits of industrial solar vary widely among stakeholders in the San Luis Valley, nearly everyone agrees that conserving water in our high-elevation desert is critical.  Tessera exclusively deploys the SunCatcher Solar Dish Stirling System, a CSP technology that it estimates will use only 10 acre-feet of water per year.  OptiSolar is proposing to use the more familiar photovoltaic (PV) technology that uses no water.  RES has proposed using Parabolic Troughs to generate heat to drive steam turbines.  According to the National Renewable Energy Lab (NREL), troughs use between 760-920 gal/MWhe, and are the highest water using CSP technology.
Tessera’s Dish Stirling technology is cutting edge but as yet unproven at the commercial scale.  However, several large projects are in the works including Solar Two, a 750 MW project on public lands in the Imperial Valley, CA.  Solar Two is currently undergoing an EIS (see:   As in the SLV, industrial solar development is being hotly debated in southern California (see:
Collectively, these solar developments will give the SLV the capacity to produce 575 MW of electricity on about 4,000-acres.  This dwarfs the Valley’s current showcase solar facility, the 8.2 MW, 80-acre SunEdison PV plant in Mosca that is itself undergoing growth.  SunPower recently teamed up with Xcel Energy to expand the site by 17 MW on 200-acres.  This exceeds the SLV’s current energy use by three fold.  Whether these projects will employ natural gas or molten salt storage systems to maintain 24-hour operations is still in question.
To transmit the solar energy Tri-State Generation and Transmission Association and Public Service Company of Colorado (PSCo), an Xcel Energy Company, have partnered to build a new $200 million, 95-mile double-circuit 230-kilovolt (kV) transmission line from the existing San Luis Valley Substation in Mosca to a new Calumet Substation near Walsenburg.  According to the June 2009 Alternative Evaluation (, the new transmission line would allow up to 1 Gigiwatt (1,000 MW) of electricity to be “injected” from the SLV.  Citizens can comment on the transmission proposal through September 21, 2009 (see:
Tessera representative Richard Knox will give a talk at the SLV Energy Fair on Sunday Aug. 30th at noon.  On Monday, Aug 31st he will host a public open house from 4-7 pm at the Saguache Community Building in the Town of Saguache.  Call (602) 957-1818 or email