[TowerTalk] Low RFI diesel generator?

[Roger (K8RI)]

On 3/27/2013 12:26 AM, R.Morris wrote:
> On 03/26/2013 09:45 PM, Rick Kiessig wrote:
>> I'm in the market for a new genset - probably a low-RPM diesel generator,
>> with 240VAC, clean sine wave output, audibly quiet / "silent" canopy,
>> in the
>> 10 to 20 KW range.
> 20 KW..? Need to run all your Alpha amps and the machine shop at the
> same time?
>
> http://powerequipment.honda.com/generators/generator-how-much-power
> ....and they sell generators.

After readig this, all I can say is BS spelled in all caps.
I would at a minimum, double their figures.

Refrif=gerators, freezers and sump pumps are energy hogs when starting 
and if more than one starts at a time you need lots of capacity.

Gas furnace, it still takes a pretty good sized fan for a forced air system.

Geothermal?  Motors and compressors..they are just a big air conditioner 
running backwards.

Electric hot water heaters? Up to 4500 watts mt ass!  We had a good 
sized one with double insulation and TWO 4500 watt elements.

We've since re insulated with foam, insulated the basement and foamed 
the end plates. Our little house (1100 sq ft) is now so efficient that 
we had two contractors tell us it wouldn't be worth the expense to go 
with geo thermal.  The payback came out to 47 years, or basically the 
life of two systems. So by the time we broke even on the firs one, we'd 
be installing the third one.

You can get away with using the running current of all the motors added 
IF they equal the starting current of the largest one and you insure 
they can not all start at once.

Generated power is convenient, but very expensive.

Solar?  Now that's really expensive.  To run our little house would cost 
on the order of $50,000.  That's solar backup to be independent of the 
grid and solar is not permitted in all areas.  There are some severe 
restrictions on both solar and wind in our township. HOWEVER Ham towers 
only have one restriction and that's that they can't fall on your neighbor.

Pay back from back feeding the grid?  It's great IF you can get into the 
system and they only let about a 100 on each year around here, but I'm 
far more interested in not having to depend on the grid in an emergency.

 > If you are talking a normal family home, grab your last few electric
 > bills and do some numbers.
 >
 > Make a list of all that "needs" to run and figure their start current.
 >
 > My 3400 sq foot, four bedroom house with most of the toys, does a high
 > average of 1kw on a 24/7, 30day month.
 >
 > My eight year old heating system pulls 3 amps on start up and drops to
 > 1.3 on run. (360 watts to start)
 > Natural gas, forced air. It has a "soft start" ramp up blower.
 >
 > My 48" LED TV does less than 100 watts.
 >
 > The house is full of CFL light bulbs.
 >
 > You don't need to run the clothes dryer, clean underwear is overrated
 > anyway.
 >
 > Honda markets a "smart" breaker panel. If it knows the refrigerator is
 > running, it does not let the freezer or furnace start.
 > Five minutes one way or the other won't make a bit of difference.
 >
 > When it's all done, for a normal, single family house, 5kw is way more
 > than enough.
 >

With a smart panel, maybe. I burned up an 8 KW generator in an 1100 sq 
ft home and that was just running essentials.. Hence I'm going to a 15 - 
25 KW backup.  Hot water is gas and on demand.  Now that saved a bunch. 
furnace is high efficiency, natural gas. Dryer is also natural gas.
Lights are all, either fluorescent or CFLs.

Most exterior lights in this neighborhood are on motion detectors, so 
it's usually nice and dark except for the light pollution from town. 
I've not had the 10" Meade out of the shop in years.

Thing is, whats the cost to convert appliances and go to a smart panel? 
  Don't forget insulation and windows.

If you have an older home it can run $20,000 to $30,000 just to upgrade 
the house before you get to the backup systems.

If you have an old home it really is likely to be cheaper to just build 
a new one.
 > My 4kw Honda did just fine for three days. Book says 16 hours on a tank.
 > I did 18 between fills and not empty.
 >

I have dual panels so when the transfer switch is energized only what I 
consider essential circuits even have power.

 > Lots of fuel spinning that other 15kw....

I use very little extra fuel running the larger generator and a lot less 
than when over working an under powered system.

Another thing to consider is "do it your self" which we can.

73

Roger (K8RI)
 >