Backup Generator Project
ON HOLD
So, after living a few days without power this year, and being spared by Dennis I’ve decided that we need a backup generator in case it happens again.
The Plan:
What do we NEED to run in an emergency? The listing below are peak watts. In theory none of the appliances will use 100% of their circuits, some may use more for startup.
Air Conditioner – 11,000W
Refrigerator – 1,650W
Total needed 12,650W
What else do we want?
Computer/TV/Some Lights – 2,200W
Total peak 14,850W
Normally I’d like to have 20% room to grow which would require a 20KW genset, however I know that going from a 15KW genset to 20KW genset would cost quite a bit, as a larger motor and genset are both required.
Well, checking prices on 15/20KW generators at the local hardware store gas models ($2000+) vs e-Bay DIY diesels ($1400) I’d rather go with one of the DIY e-Bay models. Diesel motors are more reliable and are more efficient at lower RPMs. Besides, this would allow me to use waste vegetable oil, or even home made biodiesel if I wanted.
The sets that caught my eye on e-bay are the ChangFa 15KW Diesel Engine / Generator sets. They can be had off of e-Bay for $1400 shipped (freight shipping is almost $400 because they weigh 1000lb). They require major assembly as they are simply ChangFa diesel engines (very good actually, single cylinder, liquid cooled, German Designed and Chinese built) and a “matching” generator. The kits come with practically an entire set of spare parts and tools to rebuild / work on the motor and the reputation on the Internet seems good.
This guy on e-Ebay sells the sets. Not any more (2006/08/24), in fact I can’t seem to find anyone selling these sets on eBay.
A few places that are using the ChangFa sets, or talking about them:
James Lerch’s Project http://lerch.no-ip.com/ChangFa_Gen/
UPDATE James has gone through a year of using this genset and has some nice data on fuel usage and output, looks good. Average cost of operation at peak load (~10kw) is $0.31 / kwh (Based on $3.02/gal diesel and $2.88/gal gasoline). This is lower than most all commercial gensets, except for the Kohler Marine Diesel which is around $0.27/kwh, and I can assure you that you’re not getting that for anywhere near $2000. It’s interesting to note that all of the gasoline generators use almost twice the amount of fuel, and as a result cost twice as much to operate. If you’re looking at a 72 hour outage, you’re probably talking about $250 (roughly $83 a day) savings for using Diesel as opposed to gasoline. The power quality, however, looks horrible. Definitely needs a rectifier or something. Might be hell on electric motors, PCs can probably take it, especially if you’re using a UPS.
That’s all for now…
