Digging up the lawn again?
Digging up the lawn you say? Yes we are, and we're getting quite good at it too, as we proved last summer! This time around we're working on a serious overhaul of the heating and hot water systems for Cedar Lodge and our maintenance shop. How is it all going to work? Well, this requires us to backtrack a bit, but read on...
When we put together our snowmaking system last year, we installed a 200 kilowatt diesel generator (running on locally produced biodiesel) to power the pumps and snow guns, as three phase power isn't available here on the grid. In general, internal combustion engines aren't very thermally efficient, which is to say, they make a lot of waste heat. In our case, that number is well in excess of 600,000 BTUs per hour (a LOT of heat), all of which we had to send out the window last winter.
Thanks to this project, all of that is going to change however for this coming season. We are in the process of installing a waste heat recovery system on the generator, which will take the heat from the engine coolant, exhaust, and intercooler, and funnel it all into a massive hot water system. The heart of this system will be a 10 million BTU thermal reservoir, in the form of a 20,000 gallon insulated water tank, buried in the east lawn of Cedar Lodge. From this tank, we will draw hot water to heat both Cedar and the shop, as well as provide all of Cedar's domestic hot water.
How are you going to provide heat when you're not making snow? Good question! In addition to all heat recovery work, we're also installing a very large solar thermal array on the roof of the pump house/grooming shed, which will provide almost all of our hot water needs during the summer months. Should we find ourselves in the midst of a cool cloudy period, we'll fall back on high efficiency wood gasification boilers. Right now we have one of these boilers in our snowmaking pump house that we have used to heat the adjacent shop for the last few years. It works on the same principle as the larger system we're currently putting together: heat up water in an insulated tank, and then run it through radiant floor as needed to warm the building. This boiler will be joined by a much larger one this fall, and the two will work in tandem as needed to provide hot water for the thermal reservoir when we're not making snow, and it's not sunny enough for the solar array. We'll be able to fire up one of the two wood boilers for a few hours, and bring the water in the reservoir back up to temp, ensuring that everyone will still get a hot shower when they want it.
At this point, (following months of extensive planning) we've done the bulk of the serious excavation, and should be starting concrete work on the thermal reservoir early next week. Stay tuned, we'll be posting updates as things progress.