By any measure, the construction of a ten-thousand square foot residence is no small undertaking. Neither are the resultant energy bills, given the demands of five internal air conditioning units and all the requisite household appliances. Faced with a utility bill of over two thousand dollars each month, the Laursens knew they had to do something. They have successfully installed the largest photovoltaic residential system in California.

Andy Laursen and his family wanted to find an ecologically sound and self-sufficient way to provide for their power needs. Andy also wanted to provide power for his home for generations to come while insulating himself from certain future increases in electricity rates.

Once the Laursens saw the advantages of going solar, they decided to go big. The initial design called for a generating capacity of 45 kilowatts, entirely produced with photovoltaics. This was installed during the height of the California energy crisis in the Summer/Fall of 2001 and immediately reduced their energy bills by 90%.

Spurred on by the success of this first installation, Andy commissioned another 12KW PV plant to power a newly constructed guest house and the remaining household requirements in the summer of 2002. Finally, he completed the installation by adding another 2KW PV system to pump water to a pond where wildlife come to drink.

This huge residential system was a great success for the Laursens, and for Sierra Solar Systems who provided the equipment. The family has now completely eliminated their high utility bill and will be powering their home for generations to come with clean renewable energy. In addition, local wildlife will receive the benefit of a year-round drinking supply.

The Laursens' solar arrays were provided by Sierra Solar Systems and installed by Felix Electric in Grass Valley. California Energy Commission rebates reimbursed the Laursens for about 38% of the total costs of their 57 KW array, and additional rebates from PG&E for large systems should reimburse them for another 6%. They will also receive a 15% state income tax credit.

Equipment:

• The original 45 KW system consists of 300 BP-2150 150 watt PV modules and 15 Sunny Boy 2500 watt inverters,
• The second 12 KW system consists of 72 Schott Applied Power 165 watt PV modules and four more 2500 watt Sunny Boy inverters. System parameters are monitored by a Sunny Boy control module and PC connection in the house.
• The pumping system consists of 16 Kyocera KC-120 PV modules mounted on a dual axis Wattsun tracker powering a Grundfos SunSub PV powered submersible well pump.