diesel or gasoline generator for home emergency power? - Page 2 - PeachParts Mercedes-Benz Forum

Actros617 · #16 11-04-2008, 10:44 AM

Go with diesel, is safer and efficent. If diesel is too expansive than make biodiesel for it... Save even more money and make you yard smell like fries

!!!

nazrat · #17 11-04-2008, 10:52 AM

I went with Diesel for a few reasons:

1) It hardly ever goes bad if treated properly
2) Hard to ignite outside of the engine. Heck it's hard to ignite inside the engine too!
3) Most consumer gas generators are junk. They aren't designed to last very long. I plan on staying here for a long time and don't want to have to replace the whole unit (ever).
4) Most diesel units are 1800rpm instead of 3600rpm. This means they are quieter (ok, it's all relative) and will last longer than the faster turning engines.
5) By design diesels have to be tougher. This translates to durability.
6) I had a diesel car as well. That is gone now but it's still just as easy for me to transport diesel and I don't have to smell gasoline in the car when I do.
7) Diesel generators run a LONGER time on the same volume of fuel than a gasoline generator will. You'll notice this is especially true when the generator is running at low load. The minimum fuel used by a diesel is far lower than that of a gas engine.

-Tad

babymog · #18 11-04-2008, 10:58 AM

I've had propane and diesel generators, never another propane (LP).

The LP has the lowest amount of BTUs/gallon, has to be transported under pressure, and not everyone has it. If you are going to try and fuel it from 20# gas-grill tanks, get a lot of them.

Gasoline and LP generators are usually built cheap, "throw-away" generators. However, they are also cheap to buy per KVA compared to diesel. Gasoline is easy to find most of the time and easier to transport than LP tanks.

Natural gas is the best, if you're plumbed for it, but of course there is no transportable supply so if you're looking for a natural-disaster type generation, not always reliable.

Diesel is IMO the most reliable and durable, provided you can find and store the fuel. As others have mentioned, you can even mix up your own fuels for it with a little research. Stinkier and more expensive than CNG or LPG generators, but if it's for backup use, not regular use, that's expected anyway.

Motorhead · #19 11-04-2008, 12:43 PM

If at all possable, go with a 1800rpm unit. Propane or Nat. gas is a good way to go. I have a 7.2k Military genset for my house. It was built in 1968! Right now I run it on gasoline. I have a 16 gallon barrel with a military gas can adapter. I also had a transfer switch installed at my panel so I can use the plugs in the house. The only drawback is the genset runs at 3600rpm. Luckily I installed it in my carport and you don't hear it much in the house.

1985Az300DTurbo · #20 11-04-2008, 03:28 PM

Thanks again for the insightful feeback. Frankly, I was surprised that diesel didn't pop to the top of everyone's list, but now I see why. I do not have a convenient source of natural gas. so...Propane absolutlet makes sense from a clean burning/low maintenance perspective. I also really like the idea of alternative fuels for a diesel generator (PVO, WVO, biodiesel, keorsene, etc.). Our warm climate and mild winters really makes it a lot easier to consider the alternative fuels.

Jerzeeshor · #21 11-04-2008, 03:31 PM

If natural gas was available, your choice would be a no-brainer!

In the alternative, ask anyone in hurricane alley in Florida this question and you will get a resounding answer...PROPANE! It stores safely. Never deteriorates. Is always available to be delivered to your tank from the truck! And you can also use it to power your pool heater, gas grill, stove-top, oven, hot water heater, etc.

Gas and diesel become a high-demand commodity when the electricity goes out! Most governmental and commercial operations rely upon diesel to power their stand-by generators, and they get first preference from the suppliers, who then must ration their existing reserve of the fuel to the general public. It's not fun waiting hours on-line at a local gas station to re-fill a few 5-gallon jerry cans of the stuff for a hungry whole house generator when your home tank runs dry!

And forget gasoline-powered gensets unless your needs are to intermittantly run a portable to fire-up a refridgerator or a coffee-maker! They are just too dangerous for whole-house operations!

Jeremy5848 · #22 11-04-2008, 03:52 PM

Quote:

Originally Posted by babymog

I've had propane and diesel generators, never another propane (LP). . .

While gasoline and diesel fuel both have more energy per unit weight than either propane or natural gas, we're talking about emergency generators here. Reliability is more important than efficiency. Propane, BTW, has more energy than natural gas, since its molecule is bigger than the methane molecule that constitutes most of natural gas.

The other important question that each of us must answer for ourselves is, what fuel do I already have available? I installed my propane-fueled generator because I had propane on the property to run the house (I wouldn't put in propane just for a generator). That was years before I discovered diesel cars or I might have made a different decision. Having two diesel cars and a diesel tractor means always having fresh diesel fuel on the property.

Another question is the availability of inexpensive but reliable generators. My Onan was a commercial unit but I was able to get it on the surplus market (7.5KW for $700). A new commercial generator capable of maintaining an entire household for several days of continuous operation will not be cheap, regardless of the fuel it is designed to use. If you can save a significant chunk of change by picking up a generator on the used market, I suspect that you'll take what you can get and not be picky about the fuel.

As for natural gas, it is clean and convenient but I'd be concerned about reliability in any kind of major disaster. If the gas stops coming out of the pipe, your generator stops working. For disaster preparation, I'd prefer to be entirely self-contained, with the fuel actually on my property. If my propane tank runs dry, I can always switch back to gasoline, which my Onan was designed to do.

Jeremy

babymog · #23 11-04-2008, 05:15 PM

I recently sold my back-up genset, never gets use. On top of that, I decided that my (42kva) genset would consume diesel fuel at a rate that would eclipse the cost of a luxury hotel room. Consider a 12kva genset, which would consume about 1gph of diesel, which is 24gallons/day and even at $3/gallon you would be spending $72/day, ... plus the cost to buy/install/maintain the APU.

A 12kva is IMO minimum if you want to run a house on limited power for a reasonable amount of time, if you have a 100% power factor / duty cycle, that makes around 55a @230VAC available, would run a water pump, reasonable HVAC system, refrigerator, TVs and lights if managed well.

Yes, 1800rpm, brushless, and liquid-cooled are three things I'd definately require.

dagObx · #24 11-04-2008, 06:17 PM

What he said!!!

I've had a diesel 12 kw unit at my house out here on the Outer Banks of NC. There is no natural gas out here. I was considering propane when I installed the 12 kw unit, but all I could find at the time was a 3600 rpm genset & I wasn't about to listen to that thing scream at me night & day.

I, too, had most of my high-electrical-use appliances (furnace, stove, etc. - all but the water heater) on propane, which lowered the size genset unit I needed. Pricey, though - the diesel genset ran me around $5K installed (new genset unit, electrical hookup/transfer switch).

The electrical grid out here is subject to a lot of abuse from Mother Nature. Hurricanes, nor'easters do a lot of damage. I've had to use it at least twice a year average.

Would I do different next time? I don't know, it would depend on whether natural gas was available & if I could find a 1800 rpm unit. Otherwise, it would be diesel.

Motorhead · #25 11-04-2008, 06:37 PM

Quote:

Originally Posted by 1985Az300DTurbo

3. I recognize that I will pay a few more bucks for diesel power over gasoline power but there are a number of Yanmar clone powered gen sets that look attractive out there.

What else am I missing in my thought process?

I appreciate the feedback from this forum. I wouldn't be driving a 23 year old diesel Benz if it weren't for this forum.

Mark

I bought two of those Yanmar clone single cylinder diesel gensets. They were JUNK! The one, I had hooked to the house and it ran about 45 minutes when it let go with a BANG. The balance shaft broke and went through the side of the engine. All of the wire connectors were cheap and thin. ALL of the push-on electrical connectoor were made from super thin brass and wouldn't hold the terminals good. These units were NEW. I personally like the ONAN inline aircooled 2 and 4 cylinder sets. The 2 cyl units are uaually 5-7kw in gas,diesel or vapor gasses. The 4 cyl are 10-15kw same fueling variety.

nazrat · #26 11-04-2008, 06:44 PM

I have about $1200 in my used Onan diesel. It's a 7.5kw unit and will run the well pump, pellet stove(s), TV, computer and ceiling fans. Enough to be very comfy. It also doesn't need to run 24/7. It will sip fuel at around .6 gallons/hour at FULL load, which I can't really do continuously.

-Tad

tobybul · #27 11-04-2008, 06:58 PM

Generally speaking, natural gas would be a better choice based on fuel supply. As has been said, the reason you are getting a generator is to take over when power is out. So, when designing for a situation like this, do you factor in a risk analysis or do you base it on a worst case scenario.

If you want to take the risk that power will come back in X number of hours or days, then reflect that on your fuel tank capacity. But if you design for "unlimited" number of days then maybe NG is best (assuming the NG supply is not interrupted.)

In my part of the country, the norm seems to be NG on larger home generators.

Also, check with your local power company. Some provide information on how to connect your generator and how to isolate it from their system. Some also have meter socket equipment that has a built-in switchover switch.

Jeremy5848 · #28 11-04-2008, 10:39 PM

That's right, I forgot to mention that your utility will be much happier if you have your genset connected through a transfer switch so that your generated power doesn't fry some poor Wichita Lineman.

Another good thing about the commercial gensets (Onan, etc.) is that you can always get parts and repair for them. In that respect they are like a Mercedes. The one time I had trouble with my unit, I visited a local generator place. They didn't know me from Adam and had never seen my installation but once I gave them my make and model number, they knew right what to do. Came out and fixed my problem in a couple of hours. You won't get that kind of service on a Wal-Mart cheapo.

katja · #29 11-04-2008, 11:17 PM

What about using your Mercedes diesel as a "generator?" Essentially using an inverter hooked up to the battery, and the engine to keep the battery from draining down. I thought about that a while ago as an economical solution to the periodic short-lived power outages here, where my main concern is keeping the refrigerator cold and tropical pets warm, and maybe powering the computer for entertainment

I'd just run a long extension cord inside. I would imagine that the Benz wouldn't use much fuel at fast idle, and I have a small supply of biodiesel around.

DieselClack · #30 11-05-2008, 12:01 AM

Quote:

Originally Posted by 1985Az300DTurbo

I'm considering the purchase of a 5-7.5kw generator for home emergency power and would like to know the forum members thoughts on going with diesel over gasoline power. I know this is a loaded question given the makeup of this forum, but here's my thought process:

1. I already own an emergency diesel storage system (85' 300D) so my fuel gets rotated regularly. I might even be able to talk my wife into increasing the diesel storage capacity if I can sell her on this idea

2. Diesel engines are simpler and have less toxic exhaust fumes (I believe this is true) for humans and animals outside.
3. Diesel engines are made for continuous use.

A little more background:

1. I live in Phoenix, Arizona and a summer black out is a worst case scenario in our climate. We can pile on blankets and sleeping bags in the winter but their's no escaping the heat in the summer....
2. I would size the generator to run an evaporative cooler, refrigerator, a few lights, TV, radio, etc.
3. I recognize that I will pay a few more bucks for diesel power over gasoline power but there are a number of Yanmar clone powered gen sets that look attractive out there.

What else am I missing in my thought process?

I appreciate the feedback from this forum. I wouldn't be driving a 23 year old diesel Benz if it weren't for this forum.

Mark

Go with the diesel! You can always run it on biodiesel in this state and it's available at Western States Petroleum on 16th Ave and Grand.