Life, Faith and Urban Farming

The life and happenings of an unconventional pastor and urban farmer living in the city with a family of five.

Thursday, December 29, 2016

Going Off Grid: Part 1, Heating our City Home

some of yesterday's results
There is a serious cost to energy production, always a mix of environmental costs, financial costs and labor costs. I spent the day yesterday splitting wood with a rented log splitter in our alleyway. I guess I mixed all three of those costs because I didn't split by hand this time. I was joking with my friend Chris that "there's nothing like city living" as we loaded a few thousand pounds of firewood onto the pneumatic log splitter. It was 2009 when we decided to forgo having a furnace as a big first step in going off the fossil fuel grid. We moved into a house with electric baseboard heat, basically space heaters, in every room. They are inefficient, expensive to use, and dangerous. We've had several of the kids toys nearly burn or melt when someone accidentally turned on the heat in their rooms. And so, we don't use them. When we found this house, without a gas powered furnace, it seemed perfect for us to try heating with wood, something I was interested in. I can't imagine how much energy is used to heat the buildings and houses in the world, most of it is fossil fuel generated heat that was buried in the ground for the past 300 million years or so. The problem with fossil fuels? Buried carbon is released into an atmosphere it hasn't been in for millions of years.  Burning wood that is aged and dried in a high efficiency wood stove is a great way to get away from burning natural gas or fuel oil for your heat, and it's quite clean too. Both heating methods release carbon into the atmosphere, but burning firewood releases biogenic carbon that has been captured from the atmosphere for only the age of the tree. (Note: most of the wood we burn is either repurposed scraps from a lumber mill or invasive tree species that I replace with natives or fruit trees, these threes are only about 15 years old) Biogenic carbon is captured carbon from a biological system, a living system based on decades of carbon capture. Burning fossil fuels is based on geological time, not biological, making it disastrous for all biological systems on earth. Energy from biogenic systems is a sustainable source if we are planting new trees and harvesting from well managed sites.

Using a log splitter yesterday was a first. Usually I split by hand or I buy the scrap wood from a friend who runs a lumber mill an hour away. Over the past two years I had accumulated large rounds of oak, maple and the highly invasive Siberian Elm that were all knotted and mostly too hard to split by hand. Last spring I hurt my shoulder at the gym (i.e. backyard where I split the wood) and so learned that I shouldn't try it again this year. So... gas powered log splitter on a four hour rental sounded great.

Outside the Garfield Farm bioshelter at night
Wood heat is not the best way to heat a home but it's a step in the right direction. The best heat source is probably through passive solar design, once the design is implemented in the construction there's no cost or fuel besides the sun, not even solar panels are needed. At Garfield Community Farm we built a passive solar greenhouse that never goes below 32 degrees. Most greenhouses heat up quite efficiently when the sun is out, but quickly cool down at night. Our plastic tunnel greenhouse heats up nicely, but cools very quickly at night to nearly the same temperature as the outside air. Our bioshelter greenhouse captures that heat energy of the day and stores in a variety of ways that keep the building warm all night. The north side of the building is built into a hillside, where the ground insulates and transfer warmth from the outside soil. The north side is also not clear, it's insulated with spray foam insulation. The south side is double paned polycarbonate, a better insulator than single paned glass or plastic. Inside we have barrels of water, they warm up in the hot sun and then release the heat stored in the water as the temperature drops. Inside the building the thousands of pounds of raised bed soil also absorb heat from the sun and release it into the air of the building during the cold winter nights. Maybe my favorite aspect of the boishelter's heat system are the eleven chickens that, according to Bill Mollison, are each the equivalent of a ten watt space heater. By the way, the chickens in the bioshelter also release CO2 into the building through their breathing and help the plants grow, a common problem in winter greenhouses is actually a lack of CO2 as the plants absorb it all and release oxygen. Finally, to buffer the cold nights in cloudy old Pittsburgh, we installed a pellet stove to stabilize temperatures during the dead of winter when the sun rarey comes out. These pellets are compacted saw dust from the lumber industry, a waste material that when burned is a very clean biogenic form of energy. Pellet fuel costs more than free firewood, but burns more efficiently and is much less labor intensive.

The tropics in 800 square feet in our bioshelter
If we had a newer home with good insulation and tight windows and doors our wood stove would probably heat the home with much less fuel. We use about four to six cords of wood every year to heat our 1600 square foot 90 year old city house. The best part of our house is that most of the windows face south and we have no neighbors on the south. We are flooded with sunlight on sunny days, helping warm the house with passive solar heat. New homes could be heated almost exclusively with passive solar heat if we designed them with zero fossil ethics in mind. The technology is simple, basic design for heating from the sun using clear south sides of buildings. All new construction should take passive solar heating into consideration, it could account for anything from a 10% reduction of heating to 100%.

I can't believe it's been eight years of living without electric or natural gas heating. It is definitely a way of life starting with firewood acquisition twelve months ahead of burning the wood. It's usually February that I start searching for firewood for the next year. It really makes you realize how much energy is used to heat a home when you have to carry a few hundred pounds into your house every day and control it's combustion. It's not for everyone. I'd be great if we had double the number of solar panels so we could use the electric heat in the house to stabilize and supplement the wood stove, but we don't, and so wood it is, a biogenic and sustainable source of cozy heat.

There are many other ways to heat buildings sustainably, but all of them require a redesign of our lifestyle and/or a redesigning of our buildings. That's what gets permaculturists excited. In order to transition to a carbon neutral society we have to redesign civilization, and permaculture has all the design principles needed to embark on this massive endeavor. The question is, does our society have the fortitude to embark on this journey of imaginative redesign? At this point the answer is in question here in the United States, and yet, world wide we are moving in the right direction.

And so, our family, hauls wood into the house multiple times a day reminding us that heating our homes comes at a great cost. It comes with a cost to the environment, a cost to our pocketbooks, and a cost in terms of time and work. We choose to put more on the time and work side believing that's the right thing to do. And, we get a really cozy living room that's almost always warm and beautiful.






4 comments:

Blaine said...

Thanks for this interesting post, fellow Pittsburgher! I am interested in the technicalities of your wood heating. What temperature are you able to keep the house at using the wood stove? What kind of envelope remediation have you done on the house (air sealing, blown-in wall cavity insulation, etc.)? Also, what kind of wood stove are you using? I have thought about wood heating as well to supplement gas and reduce fossil carbon emissions, but I have not pursued that path for the same reason that I would not own a diesel car here: 2.5micron particulate emissions in a city with an existing pollution problem. Have you considered heating with a rocket mass heater? I think that would solve the particulate emission problem as well as reduce the amount of wood consumed dramatically. I even read recently about an EPA approved and UL listed rocket mass heater called the liberator, which is probably safer than a self-built unit. Thanks for writing your blog and doing good work here!

John said...

Normally we keep the house at about 65 degrees. Surprisingly the heat flows through the house quite well, even though the stove is in the living room. We keep doors open when we can to circulate air. When it's really cold, single digits we know it'll be in the 50's when we get up in the morning. Our stove can burn a full load of wood for about 10 hours on a low burn so we're able to just put new wood in and get a hot fire back up and burning. Our house has blown in insulation in the walls and attic, we have basic double paned windows. The stove is a Lopi Leyden, we like it, though we've had to spend money on repairs. I love the idea of a rocket mass heater and would be very interested in learning. I read stuff and done research, but I need to see one and witness it. I also think a pellet stove is a great option for supplemental heat, they are so easy to operate and can probably heat an entire house for much of the year. Keep me posted if you try the rocket mass heater!

Blaine said...

Thanks for the info, John. I, too, would like to see a rocket heater in action in a house before moving forward! We just moved in, so there are other lower-cost, high-value efficiency improvements like blowing in insulation that we need to do first. For me, the appeal of the rocket heater is that it uses smaller cuts of wood, and it could heat our house for the winter with about a single cord. I think I could easily harvest that amount locally in a few weekends from tree-tops and other "waste" wood using an electric chainsaw. For a single cord of smaller rounds, even hand-splitting would probably not be that hard.

I see that you are an urban farmer as well. Have you read "living the good life" by Helen and Scott Nearing? In their book, they make the point that their homestead required dramatically less work because they were vegan. Apparently, most homesteading labor is spent on animal husbandry: fencing, feeding, cleaning, breeding, medical care, etc. I'm still studying the rocket stoves, but I think they may align with this simplified/appropriate/convivial technology approach.

brian said...

Hi guys - I love this blog and the discussion! About a year or so ago I became active in a non profit called Solar Cities (not to be confused with Elon Musk's company), which focuses on bringing residential scale anaerobic biodigesters to the poorest folks in 3rd world countries to provide solutions to problems such as open sewage and dangerous heating and cooking in primitive huts or dwellings.

Solar Cities have digester kits made from used IBC tanks. I plan to build one in my back yard and capture and use the methane produced for my gas grill. From what I've been told, one of these digesters can supply 4 hours of cooking fuel per day, simply by feeding food scraps from an average sized family into the digester. It seems you'd have much more fuel to feed the digester than that, based upon all your greenhouses. One of the founders of the group uses a 2 burner, counter mounted burner daily. Might be a fun option for you to try out. It's amazing to see a use for our food and plant waste to replace fossil fuels.

I'm an architect by trade, and have been pondering ways to use a digester in my next home to replace septic, and provide heating and cooking fuel as well. I plan to design and build a Passive House (not just passive solar, but this program is the most stringent energy performance standard in the world) to reduce our heating and cooling needs by 70-90% right off the bat.

Thanks again for your blog! I love it!