It’s been a busy week around here, although, one could argue that every week around here is a busy one. We installed a new battery bank this weekend and I thought that we might share a bit about our off-the-grid power system. Pictures included!
About ten feet from our home is our “hydro-house”, which is a small building that houses our hydro-electric system and all the necessary components for converting the power into “regular” power for “regular” home use.
There are two 24 volt turbines in the lower part of the structure, one fed by a 4″ penstock (fancy word for pipe and only used when the pipe is used for the generation of hydroelectric power) and the other line being 3″. Off the 3″ line are two 2″ tees that supply water that feeds 2″ mainlines which supply water for irrigation and can be fully utilized without a reduction in power output (Again, make the resources you have the most efficient possible). At full output(varies in response to the battery “state of charge”, i.e., drops as the battery charge increases) they produce 90 amps of charge at 25.6 volts, or 2,304 watts. Volts X Amps= Watts
On the left wall are a series of electrical devices and breaker boxes,as well as the battery. We just installed the battery pictured on Saturday, as the old one bit the dust after eight years of service. The one we replaced turned out to be undersized a bit (637 amp hours) and one cell started going bad about three years ago which prevented me from equalizing the bank with a controlled overcharge. The process of battery equalization is done to desulfate individual plates in each cell that combined, make up the battery. Without this maintenance practice employed approximately every thirty days, battery death comes prematurely due to plate sulfation. These two strikes made the third inevitable, so it was out with the old and in with the new.
The new battery is a 24 volt battery (made up of a series of 12 – 2 volt industrial cells combined to make a 24 volt battery) and has 1100 amp hours (20 kilowatts). It weighed in at a hefty 1,800 pounds versus 1000 pounds for the old one. And yes, installing it was an adventure. The process was well-thought out ahead of time and took four of us three and one half hours to remove the old battery and install the new. Without our 1845C Case skid steer loader and the luck of buying a forklift attachment for it back in ’04, this would have fallen into the category of “Not doable.” This new battery should last 10-15 years.
As an aside, a 12 volt battery at full charge is actually 12.8 volts, a24 is actually 25.6 and so on as the voltage goes up. A “12” or “24”volt reading actually means your battery is dead with a capital “D”, and with those sort of meter readings you just got out the Visa card whether it’s a Deep Cycle battery or a battery in a vehicle. Constant metering and maintenance is required.
More in a following post on all the amazing gadgets on the wall that make turning water into power for your home computer possible.