[email to a blog (Instapundit) ]


Having enjoyed about one-third of our lives on generator power, we decided
to enter the discussion.


I have more than 40 years experience in electric power generation for prime
power applications (seagoing vessels, forward operating bases, field
hospitals) and critical standby power (healthcare facilities, emergency
services, credit card transactions).

My wife has invested a similar amount of time performing research at sea,
and in remote locations, on generator power.


We met shortly after 9-11, and we watched the Pentagon smolder for several
weeks.

Note to deniers: It really happened!


This e-mail is my contribution to the generator discussion.

First, to all those who want a cheap, convenient way to charge their cell
phones and other portable electronics: every motor vehicle includes a one
kilowatt (1kw) alternator for battery charging.


Some vehicles are slightly less (a skinny kilowatt) others are quite a bit
more (2kw) but all vehicles have a battery charging alternator.

The best way to charge portable electronics is to idle your vehicle and use
12 volt DC chargers.


To charge your cell phone, you do not even need to start your vehicle. Just
plug the cell phone charger into your vehicle and let it charge.

To charge larger items, start your vehicle and let it idle.


To operate larger items which require 120 volt AC power, such as your
computer UPS, a drip coffee maker, or a small microwave, use a 1200 watt
(1.2kw) inverter – available everywhere for less than $100.

Most vehicles today will run a 1200 watt inverter indefinitely while idling,
but you may need to turn on the air conditioner (which increases the engine
idle) or turn up the idle speed (not legal – do not do this) to make sure
the alternator is putting out full power.


Also, the family minivan (or coupe, pickup truck, or SUV) is the best
survival pod ever invented – heat, air conditioning, lights, etc. You
already own it, and the fuel to run it is negligible compared to buying,
maintaining, and feeding a generator.

Even more important, you can drive the vehicle to a fuel point to refuel it,
and charge the battery while driving to and from the fuel point.


If you need more power than your vehicle produces, then and only then,
consider a generator.

We can discuss how to size a genset for home use, based on how many items
you desire to run during a power outage, and how much fuel you are willing
to store and consume.


You can use a portable generator, or install a standby generator.

Whatever you do, please follow all safety precautions with respect to
electrical hazards, thermal hazards, and fume hazards.


If you use a portable generator, please use extension cords to power your
loads – do not energize your home wiring unless you have installed an
Underwriters Laboratory (UL) listed transfer switch!

I will discuss transfer switches later in this article.


If you choose to install a standby generator, and you live in an urban, or
dense suburban area, a propane (bottle gas) or natural gas (city gas)
powered system is the most popular and cost effective way to go. It is also
the quietest.

Note well: City gas is often shut off during natural disasters. Propane is
stored on your property, and can be stored indefinitely.

If you live in a rural area, you can go with a propane or a diesel unit, or
if you have a tractor, a pto-driven genset.

For almost all tractor owners, I recommend a pto-driven genset. If you buy a
Winco, Onan, or similar high-quality pto-driven genset, you can pass it on
to your grandchildren. It will never wear out.


The beauty of a pto-driven genset is that many tractor owners are already
adept at maintaining their tractors. Also, you can always find someone to
repair a tractor, or, if you really need to, you can buy another tractor,
new or used, almost any time.

It is extremely important to have a generator big enough to start and run
your rotating loads, and to hold frequency and voltage as near constant as
possible.

All rotating loads – well pump, pool pump, air conditioner/heat pump
compressor and fan motor, refrigerator and freezer compressors and fan
motors – require 60 hz alternating current (AC) to operate at the correct,
constant speed, and require full voltage (120 or 240 depending on the motor)
to operate at the correct current under load.


Incorrect voltage, and incorrect or varying frequency, can lead to failure
of rotating equipment.

Let me put that more plainly – a badly regulated generator will burn up
expensive motors!


Home electronics (tv, computer, etc.) are not as sensitive to voltage, and
are relatively insensitive to frequency (they all have power supplies that
convert AC to regulated DC) but they can be damaged by very low or high
voltage.

Most important is your transfer switch.


After the transfer switch is installed, and inspected by your county
building inspector, send a copy of the electrical inspection to your
insurance agent – 2 reasons:

1. Liability – If anyone is ever injured or killed while working to restore
power on your distribution grid, you will have proof that there is no way it
was a backfeed from your generator.


2. Risk Reduction – If you ever have an electrical fire in your house, you
will have proof that the transfer switch was properly installed and
inspected.

My advice is to install a 200 amp (or whatever size your home electrical
service is) manual transfer switch.


That way you will be able to use any lights, anywhere in your house,
including in your basement, regardless of whether you power your house with
a 5kw or a 50kw genset.

I do not recommend an automatic transfer switch for home use.


You want to determine that the power really is out, and will be out for more
than a few minutes (or hours).

You want to start your genset and make sure it is running right – all engine
gauges (oil pressure, battery voltage, coolant or cylinder temperature) and
generator gauges (voltage, FREQUENCY, current) registering correctly, and
then and only then transfer the load.


If the engine parameters are incorrect, you run the risk of destroying the
engine. If the generator parameters are incorrect, you run the risk of
destroying expensive items in your home.

Even if you never have a power outage, throw your transfer switch once a
year to make sure it moves.


Also, open it once a year and blow out the insects. Leave a piece of no-pest
strip or a livestock ear tag with pyrethrins in there to keep it insect
free.

I recommend testing a home generator twice each month.


Just connect an electric stove or similar load to it, and run it under load
for 30 minutes.

If you can start it and run it every 2 weeks, and it takes a full load, you
can depend on it for a power outage when you transfer the house load using
your manual transfer switch.


Takeaway – Generating your own power during an outage requires serious
investment in time and money, and significant fuel and maintenance expenses.

At present prices, we spend about $90/day for fuel and oil changes during
extended power outages.


We can discuss this stuff further if you like.

We have a 200 amp transfer switch to transfer our house between the electric
grid and generator power, and a second 100 amp transfer switch to transfer
between main generator and auxiliaries. Main generator is a 15kw 1800 rpm
diesel. Auxiliaries are 25kw Winco pto unit (more power than either of our
tractors can provide, but superior motor starting capability), 8.5kw 3600
rpm gasoline powered welder, 3.5kw 3600 rpm gasoline powered welder, 2kw
1800 rpm continuous rated gasoline powered genset (perfect for overnight
refrigeration and entertainment loads, if we don’t need heat or air
conditioning).