Page 134 - Zero Net Energy Case Study Buildings-Volume 2

CASE STUDY NO. 11
THE EXPLORATORIUM
Renewable On-Site Energy Supply
5,874 solar photovoltaic panels rated at 245 watts per panel and installed over 80,000 sq. ft. of building roof provide the renewable on-site energy supply. This installation is rated at 1,400 kW (DC), which is approximately 1,250 kW (AC) after inversion. This exceeds the utility’s net meter- ing limit of 1,000 kW (AC) by 250 kW (AC). The Exploratorium uses the separately circuited 250 kW (AC) directly on-site without any storage and relies on the connection of the remaining 1,000 kW (AC) to the utility for net metering operation.
Once the design had been scoped out and modeled, analysis indicated that the building roof provided enough area suitable for good solar exposure for the solar panels to generate sufficient energy to offset the building’s demand, achieving the ZNE performance goal. However, a num- ber of factors led to a reduction in the number of panels allowed, a change in their optimum tilt angle and in their production performance.
• The large roof monitor that provides daylight to the interior along the entire length of the building also shades a substantial area on one side of the roof adjacent to the monitor.
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Zero Net Energy Case Study Buildings: Volume 2
PHOTO: AMY SNYDER ©EXPLORATORIUM