Inderkum High School Generates Clean, Reliable Power with SunPowe

Inderkum High School is proud to be putting its principles into practice by creating a school environment that integrates sustainable and environmentally-conscious building design. By deploying measures such as solar power and energy efficiency, Inderkum is truly a model for public education in the 21st century.

– Ron Zimbalist, Principal, Inderkum High School


Natomas Unified School District in Sacramento, California, has created a new model for public education–a 21st century high school. The newly constructed Inderkum High School was completed in the summer of 2004. With a focus on academic excellence in a safe and supportive environment, Inderkum High School students are preparing to become productive members of a rapidly changing global society.


School district administrators wanted to demonstrate how smart energy strategies could complement Inderkum High School’s contemporary academic approach while simultaneously lowering its operating costs. The school’s design was modified to accommodate solar photovoltaics (PV), energy efficient lighting, geothermal engineering and low reflectivity glass.These systems would also exist as educational tools for the students of Inderkum High School.


A large-scale solar photovoltaic (PV) system was chosen by the Natomas UnifiedSchool District as a key component of the school’s energy portfolio. Solar energy was specifically chosen to provide clean, renewable power for the school, reduce operating costs and benefit the environment.

Inderkum High School’s rooftop solar array covers a combined 33,500 square feet of roof space, and is currently the largest solar electric system installed at a high school in the nation. The 467 kilowatt (kW) system produces the equivalent electricity during the daytime to power more than 450 homes.

Installed in June 2004, the solar electric system makes use of an unused asset. the roofs of the school’s buildings to generate clean, reliable electricity, especially during peak demand times when the utility grid is most constrained and electricity is most expensive.

Photovoltaic System Description

The rooftop photovoltaic (PV) array installed at Inderkum High School produces up to467 kW under peak sunlight conditions. The array is made up of 2,456 solar electric tiles and each tile has a maximum rated output of 190 watts. There are 8 tiles per string and 307 strings.

The photovoltaic system at Inderkum High School is a lightweight building-integrated photovoltaic roofing assembly that is installed over an existing waterproof roof membrane.

There are two different type of solar rooftop systems installed at the school. The system installed on the flat roofs features the SunPower® PowerGuard® rooftop system,with interlocking panels that lie flat on the roof without penetrations. The solar array installed on the sloped roofs feature a DSA approved mounting system, and integrated seamlessly into the architecture of the building, without distracting from the aesthetics of the design.

Project Overview

Location:    Sacramento, CA
Date Completed:    June 2004
System Peak Capacity:    467 kW
PV Surface Area:    33,524 square feet
Number of PV panels:    2,456
Products:    SunPower® PowerGuard®


By adopting reliable, sustainable power, Inderkum High School demonstrates that public institutions can contribute to efforts to make our nation’s energy supply increasingly emissions-free. In addition to generating electricity, the solar rooftop system provides thermal insulation and protects the roof from the damaging effects of weather and UV radiation.These benefits result in decreased heating and cooling energy costs and extended roof life.

By avoiding the purchase of fossil-fuel generated electricity, Inderkum High School’’ssolar electric system spares the environment from tons of harmful emissions, such as nitrogen oxides, sulfur dioxide and carbon dioxide, which are major contributors to smog, acid rain and global warming. Over the next 30 years, the solar generated electricity will reduce emissions of carbon dioxide by almost 4,300 tons. These emissions reductions are equivalent to planting over 1,200 acres of trees or not driving 10.8 million miles on California’s freeways.