POWER GEN REPORT IV
Gaseous Fuel Becoming More
Natural For Smaller Gen-Sets?
Gaseous fuel drivers, such as this closed
power unit from KEM, are finding
increasing use in standby gen-set
applications under 500 kW, accord-
ing to Power Systems Research.
BY JOE ZIRNHELT
There is an old mantra about how you can have a product “fast, good and cheap — pick
any two.” That tradeoff seems to be
no different when it comes to selecting power sources for standby generator set applications.
Diesel power has typically been
chosen — more than 90% of the time
— as it comes closest to fitting all
three parts of the product equation. It
is widely available from any gen-set
builder (fast), offers quick load acceptance (good) and often has been
more cost effective when considering
first cost (cheap).
Despite all of the positives to
support diesel as the fuel of
choice, it appears the tide is turn-
ing toward natural gas for standby
power applications. This is driven
by a number of factors but most
importantly some innovative product
technology, the new RICE NESHAP
regulations and a wider availability
of product alternatives.
If we focus on applications 500
kW and smaller, there are a num-
ber of factors driving this change
in product technology. Interestingly,
fuel cost difference between diesel
and natural gas is not one of them.
The availability of natural gas sup-
ply, however, is a consideration
because throughout North America
(and many other developed markets
for that matter) gas is available just
about everywhere. It comes fresh,
in a pipe to your home, office or fac-
tory, and the quality of gas supplied
by utilities is generally consistent
and an effective source of fuel.
Conversely, if we consider diesel,
the availability of a ready fuel sup-
ply can be a challenge for standby
applications. Fuel is often stored in
large tanks, which can be problem-
atic because the fuel supply often
does not get used for long periods
of time and fuel quality deteriorates.
Supply tanks require treatment, and
the challenge of keeping fuel fresh
and readily available is not an insig-
nificant aspect when considering the
total costs of standby operation.
continued on page 14
2010 U.S. Gen-Set Production
Engine Power Source Diesel Gasoline Gas
< 5 k W 7613 430,802 16,870
5 to 18 k W 6130 80,979 31,447
18 to 50 k W 16,374 9052 6610
50 to 250 k W 16,775 - 2922
250 to 500 k W 2693 - 805
Total 49,585 520,833 58,654
Source: Power Systems Research
Total
455,285
118,556
32,036
19,697
3498
629,072
2010 U.S. Gen-Set Production
Portable Stationary
< 5 k W 438,415 16,870
5 to 18 k W 84,964 33,592
18 to 50 k W 19,695 12,341
50 to 250 k W 10,736 8961
250 to 500 k W - 3498
Total 553,810 75,262
Source: Power Systems Research
Total
455,285
118,556
32,036
19,697
3498
629,072
