POWER February 2015 - 32

COMBINED HEAT AND POWER
5. Captive power. Pemex's 300-MWe, 430-MWt combined cycle plant in the Mexican state
of Tabasco supplies power and steam to several nearby industrial facilities. Courtesy: Pemex
doubled since 2000, though growth has
slowed in recent years. Much of this
growth is attributable to increasing willingness
by Canadian utilities to purchase
power from independent generators. High
gas prices in the late 2000s are thought
to have put the brakes on much CHP development,
but this may change as prices
have fallen. The Ontario Power Authority
continues to encourage small-scale CHP
projects and recently issued a call for up
to 150 MW of submissions.
Brazil. Brazil's huge sugar industry has
try, with IEA estimates of around 14 GW of
potential expansion.
Small-scale CHP, especially for use in
DC, is limited in India but growing. These
applications have been increasingly seen in
large residential and commercial projects, according
to the IEA.
Government support at the federal level
for CHP is mostly concentrated on the sugar
industry. Support at the state level varies,
though some states, such as Tamil Nadu,
are actively promoting cogeneration through
feed-in tariffs.
The Americas
In the Americas, CHP continues to serve predominantly
large industrial users.
Mexico. Congeneration in Mexico has
long been hamstrung by the state-owned
character of the grid. With 75% of total
generation and the entire transmission and
distribution network being owned by national
utility CFE, CHP plants had only one
customer for their excess power, and only
if they were smaller than 20 MW. That's
kept installed capacity under 4 GW nationwide,
even though CHP potential is thought
to be several times that. Of that total, most
is owned by national oil company Pemex,
which operates more than 2 GW of captive
industrial CHP at its fleet of refineries and
petrochemical plants.
But there is room for growth and optimism
with the recent reform of the Mexican
energy market (see " Can Mexico's Electricity
Reform Deliver on Its Promise? " in the
32
January 2015 issue), which includes the
breakup of CFE. Both large CHP providers
like GE and small-scale CHP firms like
Tecogen are said to be eyeing Mexico as a
prime growth opportunity.
The nation's largest CHP plant to date,
the $550 million, 300-MWe, 430-MWt
Nuevo Pemex plant in Tabasco, came online
in 2013 (Figure 5). The two-unit combined
cycle plant, built by Abengoa and GE, sends
power and process steam to an array of Pemex
facilities nearby, with excess power going
to the grid. Pemex's long-term goal is to
develop enough cogeneration to become selfsufficient
in its heat and power needs.
CHP is considered to be renewable energy
under national law and enjoys benefits available
to other renewable resources.
Canada. As a mature energy market in a
cold climate, Canada has long found uses for
CHP. According to data from the Canadian
Electrical Association, CHP supplies about
7% of national electricity consumption. Of
the approximately 6.5 GW of installed CHP
capacity-comprising about 200 facilities-
two-thirds are in Alberta and Ontario. In Alberta,
most CHP serves the province's large
oil and gas sector, while in Ontario it serves
a mix of industrial and commercial needs.
Nearly all of the rest is in British Columbia
and Saskatchewan, mostly serving the forest
products sector. Canadian utilities own
about 45% of the capacity, with 23% operated
by the paper industry and 16% by the
oil and gas industry.
Installed Canadian CHP capacity has
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long operated biomass-fired CHP plants,
which constitute the majority of the country's
installed CHP capacity, making up
about a quarter to a third of the total. The
plants operate on by-products of sugarcane
processing (known as bagasse), and so much
of it is available during harvest time that
the Brazilian sugar industry has long been
virtually self-sufficient in its power needs.
Advances in efficiency have increased the
amount of power generated by the sugar
industry (including the ethanol sector), and
new discoveries of natural gas offshore of
the country are expected to drive further
growth in CHP.
Future Possibilities
Globally, the requirements for future growth
in CHP are similar to those in the U.S.,
namely policies and incentives that give
CHP appropriate credit for its efficiency
gains and carbon emissions reductions over
conventional thermal generation (see " CHP:
A Rocky Path for a Promising Approach " in
this issue). However, classifying fossil fuel-
fired CHP as renewable energy or allowing
it to participate in renewable incentives,
though a popular approach in some regions,
remains controversial.
Environmental concerns and increased
availability of natural gas are likely to
mean that most future CHP capacity in the
developed world, and a growing portion
in the developing world, will be gas fired.
Biomass- and biofuel-fired CHP should see
continued growth but will be constrained to
areas where such fuel is readily available.
Solar-powered CHP shows potential, but it
remains to be seen if it can become competitive
with other resources.
Technological advances in the near term
are likely to be confined to incremental efficiency
improvements. Next-generation CHP,
such as that relying on fuel cells, and more
advanced approaches such as supercritical
CO2 (see sidebar), offer possibly but will
remain niche resources until costs become
more competitive. ■
-Thomas W. Overton, JD is a POWER
associate editor.
POWER | February 2015

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POWER February 2015

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