I thought I'd update everyone with the progress of this experiment. We are now at the 6-month mark. I started this on 8/17/2009 and today is 2/19/2010.
Winter has made some things tougher and some things easier. I no longer have to run the generator and air conditioner to keep the van cool. On the other hand, for the last couple months, the inside of the van has been around 15F-19F in the mornings.
When I start the day, I kick on the space heater for a while. This gives me a sense of warmth as it heats up the area closest to me. However, when it's that cold, a 3,000 BTU heater is going to take a long time to get it from below freezing to above freezing. When it is 40F out, it can actually heat the van from 40F to almost 60F in a 20 minute time span.
Over the last couple weeks, I have taken to starting the van itself up and letting it run while I wait inside work. I don't completely trust letting the propane heater run by itself without supervision. Utilizing the gas engine is more expensive, but considerably safer (in my opinion). The van's heater can warm up the interior well above freezing in under 30 minutes.
In reality though, heating in the morning is almost unnecessary. If I buckle down and force myself, I can be changed and inside my sleeping bag within a couple minutes. Within 5-10 minutes, the inside of the sleeping bag become suitably warm. It can be 19F in the van and 60F inside the sleeping bag around my feet.
As the day progresses, the sun comes out and warms the van considerably. As peak sun, the van can reach 60F on a sub-freezing day. If i wake up prior to 3PM, I can enjoy this warm climate. However, after 4PM, the sun wanes and the van temperature starts dropping down into the 40s. At this point, the heater is necessary to maintain.
What I should do is go to the gym immediately after work, instead of after sleeping. However, I find that dealing with putting together a gym bag and other rigmarole in the cold morning to be a nuisance. Perhaps I'll be able to adjust my patterns before winter ends. However, in the summer the opposite should occur. In the summer, going to the gym in the afternoon avoids the heat and ensures that any sweat gained during the hot day is washed off.
Dealing with the cold is easier and cheaper than dealing with heat. My own body generates lots of heat, which can easily be trapped around me.
Finally, a financial update. I have updated my equipment page with full details. For just a quick rundown, I have spend $2,856 on equipment to date. My operating cost to date has been $890.62. Looking at just operating costs, I spend $148.43/moth. A good portion of that operating cost was in fuel between August and December (the cost of traveling). If you factor out the cost of travel, operating costs drop to $275.70 or $48.45/month.
If you factor in the sunk cost of equipment, the total monthly cost breakdown is $624.44. Omitting travel costs, my monthly breakdown is $524.45.
A few things are going to happen in the next few months that will add to my costs. One is that I need to get some exhaust work done. I have an exhaust leak that is rather loud. The other thing is that work may request that I take the van with me on my weekends once the weather warms up. This of course will lead to increased travel and maintenance costs. I also need to invest in a suitable roof vent.
The final part remains to be seen. I have ordered a 24V (1500W/3000W peak) power inverter and will be attempting to run my air conditioner off of it using a pair of 12V car batteries in series. If that can run the air conditioner (which I now believe to be 950W-1010W operating/2020W peak/start-up), then I will attempt to determine the run time and size of battery bank needed to run the air conditioner. The inverter is close to $200, deep-cycle batteries run close to $100 each, and the cables aren't cheap either. I would initially charge these using either the generator or power from utility lines. If all the other ifs work out, I would then look at investing in solar panels on the van roof to charge and maintain the battery bank.
I have not yet factored the cost of the inverter or batteries into my equipment as I may end up not being able to use that type of inverter (some motors require a pure sine wave to operate). I've also been seeing some 800W, 7000BTU air conditioners on the market (mine is a 9000BTU) for around $300. These were not readily available when I first started searching out air conditioners. However, if things work as planned, I could see adding another $1000-$1300 to my equipment costs.