How to get more out of 15kw

[Lukester]

I have a 15kw air cooled Generac I bought in 2006. Up here in Mass we just had a major ice storm and I was out of power for 5 days. The generator worked great but there are a couple things that bothered me a little.

1. I didn't get as much of the house powered up as I wanted to, I am limited by the cicuits on the transfer switch. I know I am barely working it as it is now set up. How can I get more lights, etc running, short of spending the money on a load transfering device?
2. That thing goes through some propane. I bought it to get rid of my vulnerability, but with only a 120 gallon propane tank I was at the mercy of the local propane dealer who was using this emergency as an early Christmas bonus.

Thanks.

[ran007]

Unfortunately, these things really waste a TON of energy. I have the same problem even with a whole house transfer switch. I simply don't use all 20KW's when the power fails, maybe just 10%. The generators normally have a 25%, 50%, 75% and 100% load levels. Since I use 10% of 20KW, I'm wasting over 50% of the my natural gas, until I use 25% of the generator.

It would be awesome if these things went into a low power idle mode until power is demanded, then the generator would turn itself up MORE incrementally.

[irq3]

I don't think there is a cheap fix. It sounds like you want a whole house transfer switch. You may be able to use some tandom breakers if the panel allows?

How much propane did you use in 5 days? Did you have multiple deliveries? Propane tanks are filled to 80% of capacity so, it holds about 96 gallons.

[Ira]

I always thought it was like cruise control on a car when you are going up and down hills. The engine tries to run at a constant RPM (1800/3600 for a generator), but it uses more or less fuel depending on if it is going uphill (increased load) or downhill (decreased load), even with the RPM's staying in a narrow band. I assumed the fuel usage can change in very small increments if only a small increase/decrease in load is detected.

I have a 5638 (22kW). It's documented propane usage is 1.0, 2.2, 2.7, or 3.3 gph at 25%, 50%, 75%, and 100%. Of course, if it is running, it will never use no propane even if there is no load.

During hurricane Ike, mine ran for four days. Everything in the house was used normally, including central A/C and water well pump. My propane usage averaged less than two gallons per hour over that time. I don't know exactly how much it used because it wasn't completely full before the hurricane, and I haven't had it refilled yet. I bought a 500 gallon tank when I had the generator installed last August. Cost a fortune to fill it up because propane was sky high due to the oil prices going up so much.

[Lukester]

I would guess I used about 120 gallons and had to fill up twice due to it being low to begin with. At one point the gas company was unsure if they could get to me and I would have ben without power, that's the part that bothered me. I doubt I put much loadon it, because the transfer switch I have really doesn't run anything. I need to get a new whole house transfer switch. What's my best option?

[pcfrisch]

I would guess I used about 120 gallons and had to fill up twice due to it being low to begin with. At one point the gas company was unsure if they could get to me and I would have ben without power, that's the part that bothered me. I doubt I put much loadon it, because the transfer switch I have really doesn't run anything. I need to get a new whole house transfer switch. What's my best option?

I have the ASCO switch. It excercises the generator 20 minutes bi monthy.
http://www.ascoswitch.com/Products/ATS/series165/165features.html

[newguy]

I have an idea for you... but it will cost a bit of $$$.

Think hybrid! You now can get a battery backup that will handle anywhere from 6KW, 12KW, 18KW or up to 24KW. If you have a short outage the genset would never need to be started.

If you have a mid to long outage, the inverter would have a monitor on the battery charge condition, and then automatically start the generator to charge the batteries. Once they are fully charged the generator shuts down.

You can also hook up solar panels to the system and have the sun power part of your house. If you do add the solar panels to the system it will allow you to take a 30% tax credit on the entire system.

If you want to know more about it, please feel free to contact me, as I have been doing the research on the products and how they work together. There is a well engineered system that is modular and flexible.

This is the way to minimize the fuel used when you are just running a nightlight!

ssvard at juno dot com

Merry Christmas!