I’ve been doing some work recently at Earth Haven Biodynamic Farm trying to bring their grid interactive system back to life. The system itself is about 10 years old and has absolutely great gear for the era. 6Kw of panels on two arrays, a pair of Schneider’s first generation conext inverters and originally a wopping 80KwHr of battery storage. It was sitting turned off for almost 2 years as they tried to find someone to fix it. I do like a challenge! So this is something unfortunately you come across in the industry; a system that was quite pricey but set up wrong for the clients needs. There are lots of factors that go into a successful design but the first one is always listening. In this case the original designer chose to ignore the fact that there was a grid already present and chose to set them up as if they were totally offgrid. A backup generator would recharge the batteries when there was not enough sun and the large battery bank would store days worth of power but the solar arrays were not big enough to ever fully charge it… They never bothered hooking up the grid to the inverter or setting up the inverter properly or explaining the system to the people paying for it and running it. The consequence was a grid interactive inverter set up with one arm tied behind its back and clients left to figure things out as best they could a generator that ran all the time and a battery bank that failed from being sulphated from undercharging. After some rewiring, and mostly reprogramming of the unit the system now uses the grid if there is not enough sun, keeps a smaller battery pack charged fully, uses as much solar power during the day as possible and in the case of an outage uses its battery reserves then can turn on the generator to recharge. All that without any input from the end users unless they want to intervene. As it should have been from the beginning… It was a rewarding experience though a little frustrating that some really nice people had to go through all they did.
Tweed Solar 