Lochsa Design can provide cost effective solutions for your Solar Electric Power System or Web site design needs.

N7ZN Home Page

Solar Power System

Amateur Radio



Living with Off-Grid Solar Power

About Lochsa Design




When I escaped from California's Silicon Valley, I decided to realize one of my lifelong goals - to live in a home not dependent on the national electric power grid. This choice requires many lifestyle changes, and I am still discovering, accepting and living with those requirements.

All of the electric power for my home is generated by this 800-Watt array of Photo-Voltaic (PV) panels.

These solar panels charge my 2,000 Amp-hour 12VDC battery bank. My battery pack is comprised of 12 Surrette KS-21 cells in two parallel strings. Each KS-21 cell is a 1,000 Amp-hr 2VDC battery cell. Six (6) of these are connected in series to realize each 12V string.

I elected to stay with a 12V battery pack for two reasons. First, I wanted to operate my Amateur Radio transceiver directly from the battery pack. Secondly, I designed my home's wiring with both AC and DC circuits. The majority of my small and frequent power needs are supplied directly from the 12VDC battery pack. This avoids the power wasting overhead of my DC-to-AC inverter.

The photo at left is my power system electronics. (I am still in the process of improving and 'cleaning up' this installation.) The large white object at photo center is my Trace SW2512 DC-to-AC inverter. This unit supplies all the 120VAC power for my home. Capable of supplying 2500 Watts (about 20 Amps), this unit generates a step-wise approximation to sine wave power, and is clean enough to actually sell electricity back to an electric utility company.

The inverter also provides a sophisticated and powerful battery charger. I occasionally need to supplement my PV array with a small gasoline powered generator. Winter weather can be pretty cloudy up here in the Pacific NorthWest.

The large white enclosure at center right is the main breaker for the inverter's DC input. This enclosure is also the system's DC wiring center. The system's DC equipment (Inverter, PV array, PV Charge Controller and DC Load Panel) are all interconnected here.

The Trace/Xantrex C-60 PV Charge Controller is just above the DC wiring Center. This unit use the power generated by the PV array to charge the battery pack (in the large wooden box). This C-60 replaces three MPPT (Maximum-Power-Point-Tracking) controllers. The MPPT technology promised increased power efficiency. However, numerous implementation issues rendered those units a poor choice in my system.

Please check back here soon, as I have recently modified my system electronics. I will add new photos as I have them processed..


Thank you for visiting my website

Last update: 10FEB2004

Created by Lochsa Design