Big Mesa Farm IS POWERED BY SOLAR

We are completely off-grid, and when we arrived there was no electricity at all unless a generator was running. We now have a gorgeous solar “micro-grid” powering every building and the farm operations. With immense help from friends (thank you Bailey Smith and Andreas Dahm) and with support from a REAP Grant (a USDA grant to help with Renewable Energy for Agricultural Production), Bruce Ackerman (aka Dad) led the charge to get us up and running. Cyril Ackerman had just finished electrician school so he did yeoman’s work with ditch digging, wiring and conduit! After about three months we were beyond headlamps with the beginnings of what is now a solid and impressive electric system, described here by Bruce.

ENERGY HISTORY OF THE LAND

It’s been fascinating to reconstruct how previous generations lived here. The native Pomo tribes hunted and gathered plants and food from the sea — travelling with the seasons from areas inland to the coast. Imagine living in what is still the wild Northern California, but before there were buildings, cars, roads or fences! The native people might have had a hand in clearing the valley.

After thousands of years the earliest European settlers in our valley emigrated from Finland, and worked with hand tools like axes and a two-man saw to construct the first redwood buildings and split-rail fences. Apparently the first building constructed was a sauna, and one can imagine that relaxing tired muscles after a day’s strenuous work was a higher priority than building the house!

The main house was built on a foundation of huge redwood stumps, and was later improved with addition of a wraparound porch and more windows. Sometime around the 1970s two small solar panels were tacked on the roof, charging a car battery and providing a few dim 12-volt lights. Later two separate, slightly larger solar electric systems were built, with a Trace inverter producing some AC power and DC used for lighting.

In the more recent era, in which the land was used for cannabis cultivation, those owners built greenhouses and a large propane generator was used frequently — the greenhouses used propane heaters and large fans to grow year-round. We’re fortunate to have the generator as back-up along with underground wiring that was put in during that era.

As we found the farm, more buildings had been built, the early ones using rough-sawn timbers from the local sawmills that dotted Mendocino County and more recent ones using standard-size 2x4s that later replaced locally-harvested wood. The lead-acid batteries in the old small solar systems were dried out from lack of maintenance, so we began building another era of power generation, to support vegetable farming!

THE SOLAR MICROGRID

A shed that had been built when the propane generator was installed, and from which underground wiring went to a few of the other buildings, was the logical place for the center of our new solar electric system. Within this Electrical Building are now 60 kilowatt-hours of lithium batteries, two inverters, and the main 240 Volt AC distribution panels. Solar electric (photovoltaic, or PV) arrays are on the roof of this and two other buildings, for 20 kilowatts of solar generation overall.

The microgrid now provides electricity to eight buildings and powers a walk-in cooler, wells and water pumping for irrigation, a woodworking shop, crop drying, housing with kitchens, and now … an electric delivery van! Caymin saw that, after we had the electric system running, our largest use of fossil fuels was by the trucks used to deliver produce. So in 2023 she bought a Ford eTransit van — one of the large-sized vans like used by package delivery services, but fully electric. The van goes out 4-5 days a week with a load of produce, to markets 30-40 miles distant, and is charged on the farm by our solar, or occasionally in the winter charged in town at a public charger. The savings in gas/diesel and annoying truck maintenance nearly offset the loan payments and in 5 years the van purchase will be cash-flow-positive.

For those interested in more technical details and operational data on our microgrid, geek out here, and contact us if you have questions or ideas!

HOT WATER HEATING AND COOKING

We use two solar hot water heaters, which also have an electric heating element in the tank that can be used to augment the solar heating in cold weather. These units are pretty elegant, using glass tubes evacuated to a vacuum for insulation, to focus the sun on a sealed copper tube containing fluid, which passively transfers heat to the water in the tank on top.

One kitchen uses a small electric demand water heater, which works well for occasional use (but is not nearly as efficient as a heat-pump water heater, which we might transition to in the future). Propane is still used for one other water heater.

We do a lot of our cooking using an induction stove, and several induction hot plates (which can be plugged into any outlet). Two kitchens still have propane ovens.

CONSTRUCTION AND MATERIALS

An often-forgotten part of the energy and resources used by buildings is from their construction. We have rehabilitated and tightened up all the old buildings on the farm, much of the lumber having been milled on-site from trees that had either fallen or needed to be thinned to address fire danger. A neighbor milled the logs using a diesel-powered portable sawmill, and after drying outdoors the lumber is worked in our woodshop. The majority of the wire and metal conduit used for the electrification of buildings was salvage. One kitchen was constructed entirely using re-used cabinets, salvage granite countertops, and salvage windows. Like most small farmers, using what we have is a way of life!

We hope this little “tour” of our farm’s energy production has been of interest. For one brief period, roughly a century, we humans have extracted vast amounts of carbon from where it was put eons ago, returning that carbon to the atmosphere and rapidly changing the climate. During that amazing century we’ve learned and developed greatly. Now we’re using that advanced knowledge to get our energy from current rather than ancient sunlight. It’s a good time to be alive.