Bohart Guest House
Renewable Energy Installation
Built 1889, Guest House Since 1998
aka Bozeman Cottage
 
Page Last Updated: Friday December 09, 2011

Back to Bohart Guest House Page

Beginning in the Fall of 2004, I began installation of a fully renewable heating system - decentralized, low-tech heat from solar and wood.  The wood came from a local furniture makers that produce about a billion btu's per month worth of oak fuel, so instead of going to the landfill to turn into wood chips, some of it went into the boiler to make heat for the house, hot tub and backyard '69 Airstream office.  Being that I don't live on site, the multiple trips every day to build fires in the boiler were too much, so in February 06 I replaced it with a vegetable oil fired boiler.  The oak firewood supply disappeared in 2010 when the furniture factory went out of business.   

The used vegetable oil into a modern looking AgSolutions 200k Btu boiler,  highly efficient and clean burning on used vegetable oil.
The boiler holds 30 gallons of water and circulates heat from the garage to the house through buried, insulated pipes.  Inside the house there is a Takagi on-demand gas water heater that takes over when the main boiler happens to shut off.

For a review of the practical aspects of this boiler unit, click here. 

The other heat source is the amazingly simple and affordable solar hot water heater:

Seido solar hot water collector tubes mounted on south-facing
roof - 8' long x 6' wide

Here is a closer look at the Seido brand solar collector - evacuated glass tubes have flat black metal plates inside that transfer heat up into the header tube where the water is circulated.  On a cloudy winter day these units produce 140 degree F water!  Sunny winter day - 170. 
I recommend flat panel solar water heaters no, which are more durable and produce more heat per sq ft of roof area, and are less expensive.

In the basement of the house there are 2 water tanks with heat exchanger coils in them for storing all this heat.  The heat gets used in the following ways:
1. By using hot water for showers, laundry, etc (domestic hot water, or dhw),
2. By heating the house (a radiator was inserted into the furnace duct so fan-driven air passes by 180-degree water on its way to the living space),
3. By the hot tub, which has underground hot water lines leading out to it (the original electric heater exists as a backup heater for the tub),
4. And by heating my 1969 Airstream Office in the way back of the yard behind the fence. 

So with the 3 heat sources and the 4 heat uses, the system gets a little complicated looking and I won't try to label all the parts,
but the blue tank on the right is where the solar heated water is stored;
the left blue tank stores the heat from the boiler or the backup gas heater;
the white box on the right is the backup gas heater, and all the 1-inch copper is the loop thru which the hot water circulates until it finds a place that needs heat. 

                                                                                      Hot Tub with all the modern characteristics except the power bill!

How did I calculate my CO2 savings? www.carboncounter.org has a handy calculator for home energy, transportation energy, etc.  The vegetable oil crop is grown which consumes carbon dioxide, so when it is burned and releases carbon dioxide the numbers balance and it is therefore considered carbon neutral.  In addition to the carbon savings at the guest house, I estimate that I've saved 16.5 tons of CO2 per year by driving on vegetable oil (see below).

I invite you to test out this system which, for the most part, runs on oil that would otherwise be trucked to Billings for filtering then trucked to who knows where to be turned into animal feed product, chapstick, or a number of other products.  I am available for new installations and would recommend starting with weatherizing, dimmer switch installation, motion sensors for lights, and many other efficiency upgrades, than solar air heating, then solar hot water.

Paul

Bozeman Cottage World Headquarters, ofr course, also heated with hot water from the boiler

If you are interested in the above, then visit my BIOFUELS page for Bozeman:  www.bozemanbiofuels.com 

The garage at the Bohart Guest House is home to my waste vegetable oil filtering (WVO) system.  I collect used deep fryer oil, or french fry oil as it's sometimes called, from local restaurants (ironically from a restaurant called the Garage up the street, which of course used to BE a garage), heat it in my garage with hot water heat from the vegoil-fired boiler, then filter it into storage drums and eventually it winds up in either making heat for the guest house or in one of my vegoil-burning vehicles.  The truck as a 105-gal secondary fuel tank (94 Chevy 6.5L turbo diesel truck) and the Suburban has a custom made 18-gal tank under the drivers side in addition to the original 42 gallon tank which I converted to store vegoil.  If you haven't heard of this, or you don't believe it, then your first questions will be:

Q   You're kidding, right?  A regular diesel engine can't use WASTE VEGETABLE OIL?
A   Sounds like fiction but let's go for a ride and then see what you say.  It's better for the engine, runs quieter and produces a fraction of the emissions of diesel burning engines.  Actually, the diesel engine was designed to run on peanut oil, this petroleum thing is just a temporary sidetrack.

Q   What do you have to do to the oil before it can be used as diesel fuel?
A   Collect it, warm it up to 90 degrees F so it will pour settle out and evaporate out any water, then pump it out of the 55-gal drums and into a 275-gal settling tank, let it rest and settle there for a week, then pump it into a filter tank where gravity moves it through two layers of bed sheets.  The filter tank is where the boiler gets its fuel, and also where the fuel is pumped from for vehicle use using an actual fuel pump and meter with an auto shutoff nozzle just like at the gas station. 

Q   Vehicle modifications?
A   The trucks have 2 fuel tanks, one with diesel or biodiesel for starting the engine, and another using waste heat from the engine to heat the vegoil in the other tank so it will flow to the heated filter, then it's fed to the engine which is already warm from running for about 1-5 minutes on diesel or biodiesel fuel.  The engine needs no modification since it was designed to burn peanut oil in 1897 by Rudolf Diesel, inventor of the worlds first internal combustion engine. 

Q   What kind of mileage do you get?  How about performance?
A   About 20 mpg, just like diesel (diesel engines are 40% more efficient than gas ones, so that's how a big 3/4 ton truck gets better mileage than the standard, relatively small SUV).  Technically there is supposed to be a 5-10% drop in horsepower, but at 330 hp it's a little hard to tell.  Vegetable oil is actually just new diesel fuel.

Q   How many miles have you driven so far on SVO?
A   90,000 as of February 2011, starting May 13, 2005

Q   How does it feel?
A   Burning oil that's grown right here at home that has nothing to do with Iraq or the Gulf oil spill, Arctic National Wildlife Refuge, or the Exxon Valdez?  Not only that, but this is oil that has already been used to cook your french fries, requires a whopping 0.1-1 miles of transporting, and creates a fraction of the emissions compared to dino diesel.  It feels allright.

Q   What is Biodiesel?
A   Biodiesel is made from vegetable oil, a little like brewing beer.  It does not require a second fuel tank or any vehicle modifications, so it's more attractive to the mainstream, but the engines are just fine burning straight vegetable oil so I went that route.  Making biodiesel is very involved compared to filtering vegetable oil:  it requires methanol (20% by volume), lye, a reaction chamber, and washing which uses one gallon of water for every gallon of biodiesel.  The water is typically put down the drain which is highly questionable at best, and you also end up with 20% glycerine which nobody seems to know what to do with.  So why go through all the trouble of making each batch of fuel when you can convert the vehicle once and run straight vegetable oil?

For much more info, visit bozemanbiofuels.com which has links to all the nationally accredited biodiesel and SVO web sites.  There's a reason the Navy burns 20% biodiesel, and entire vehicle fleets across the country are running on it, including government and public transportation fleets as well as privately owned. 

Contact Information

Bohart Guest House Pages:
Bohart Guest House Page   Read Reviews    More Photos & Video   E-mail for Info   View Map
On-Line Reservation Page

Bozeman Cottage Pages:  Main Page     On-Line Reservations     Seasons of Bozeman     FAQ       About Us