| This is one of three overview maps showing all
generating stations. This map shows the 815 generating stations
classed into one of seven categories based on the fuel they use.
A brief description is given of the nature and pattern for each
of the fuels. Further information on these fuels is given in Additional
Notes on Fuels Used for Electricity Generation.
There were 24 plants using coal in operation at
the end of 1997. They have a prominence well beyond their small
number as most are huge plants built to be a major part of the generating
system of their province. Coal-based capacity is about half of the
total thermal capacity in Canada (17.7 million kilowatts out of
a total of 32.4 million kilowatts), and makes up much more than
half of all generating capacity in Alberta and Saskatchewan.
These plants are generally situated according to one of two circumstances:
either adjacent to surface-mineable coal deposits (mine-mouth plants)
or located on bulk transport routes so that coal can be brought
to them relatively cheaply. The plants in Alberta and Saskatchewan
meet the former criterion, whereas those in other provinces are
supplied with coal via rail or ship.
There are nearly two hundred plants using a petroleum product
as their fuel. There are several distinct geographical patterns
for these plants. One pattern is that the largest petroleum-fueled
plants in the zone from southern Ontario eastward to Newfoundland
and Labrador are mainly utility plants based on heavy fuel oil or
light fuel oil; two are just over one million kilowatts in capacity.
Another pattern is that nearly all of the stations dispersed throughout
the northern and northeastern parts of Canada are small plants which
are run on diesel fuel, and whose purpose is to be the main power
source for a municipality. As these plants lie well outside the
electrical grid, their fuel must be brought in (usually by ship).
The 107 plants fueled by natural gas are found
across the main part of Canada which had access to natural gas in
1997 - roughly from the Québec (city) westward. In terms
of the technology used, these plants are almost equally divided
between steam and combustion turbine plants. The largest plants
are utility-operated plants in Western Canada, two of which are
well over 500 000 kilowatts in size.
However, a relatively large number of the plant operators are non-utilities.
Some of their plants are co-generation plants located in industrial
areas of Canada. These plants take advantage of being close to gas
pipelines so as to use it to produce electricity, and then to sell
process steam to adjacent industrial facilities.
The 40 plants using forest-industry wastes make
up most of the generating stations operated by forest industry companies.
The plants shown on this layer are mainly used to convert waste
products from their activities into electricity for use in adjacent
mills. They are relatively uniform in size - most are from 15 000
to 50 000 kilowatts in size (with the largest being 112 000 kilowatts).
By fuel, these generating stations are almost equally divided: about
half use spent pulping liquor, while the remainder use wood refuse.
The seven nuclear generating stations are all
large facilities, invariably located close to water bodies so as
to provide the cooling water needed for the process. The plants
all consist of one or more reactor units, with the common size of
the units being 500 000 to 700 000 kilowatts. The main developer
of nuclear plants in Canada has been Ontario Hydro. Its complexes
are among the largest in the world.
Hydro-electric plants make up just over half (440
out of 815) of the total number of generating stations in Canada.
These were developed when it became feasible to use a particular
hydro site. Hydro plants are dispersed throughout most of Canada.
However, two distinct distribution patterns can be noted:
- In central and eastern Canada, there are many very small plants
which were built when the need for electric power was first realized.
The developers were usually utilities.
- In the northern parts of many provinces, there are large plants
built from the 1950s through 1970s when it became feasible to
extend the grid to sites with large potential.
Most of the plants using other fuels use a thermal
generating technology, with the fuel usually being simply waste
heat, itself. There are 11 plants included here. Most are small,
but one plant has a capacity of nearly 200 000 kilowatts. This group
also includes the three wind energy plants, which, in 1997, were
found in southern Alberta.
Geological Provinces and Electricity
Canada is divided into seventeen geological provinces. For ease
of legibility, this Geological Province layer groups provinces into
three groups rather than colouring each province separately. The
groups are:
- The Canadian Shield (which is made up of seven adjacent geological
provinces)
- Orogen (mountain-building) areas
- Platform areas
The most obvious pattern is that the Shield areas of Canada provide
excellent sites for hydro-electric facilities. The Shield is a rugged
plateau whose surface and streamflow patterns create ideal conditions
for dams and reservoirs. Many of the potential sites have already
been developed, especially when these are not excessively far from
main areas of population.
Adjacent to the Shield on most sides are the platform areas: regions
covered by relatively flat-lying sedimentary rocks. The two of particular
interest here are the St. Lawrence Platform (around the Great Lakes),
and the Interior Platform (in Western Canada). The relatively few
large hydro sites in these regions are invariably found on major
rivers, in particular, the St. Lawrence and the Saskatchewan. However,
much of the Interior Platform is underlain by coal deposits. These
have been extensively used for electrical generation. Some of the
vast gas resources in this platform have also been used for producing
electric power.
Further from the Shield are the three provinces of mountain-building
(or orogenic) activity. The westernmost of these areas, the Cordilleran
Orogen, has many large hydro developments due to its high mountains
and heavy rainfall. The Appalachian Orogen which underlies much
of southeastern Canada has much lower elevations than the Cordilleran
Orogen, and, accordingly, its hydro developments are usually quite
small in capacity.
Additional Notes for Fuels Used
for Electricity Generation, 1997
Coal
Three types of coal are used for electrical generation in Canada.
They vary in energy content per unit of weight. Bituminous coal
has the highest rank (the highest amount of energy per kilogram)
of these three types, subbituminous coal has a middle rank, and
lignite has the lowest rank. Power generation is by far the most
important use for coal in Canada: two coal types mined in Canada
(subbituminous and lignite) are used almost exclusively for power
generation, while the third, bituminous coal, is predominantly used
for this purpose.
Bituminous coal is produced in Western Canada, but mainly for export
to eastern Asia: only one generating station in western Alberta
uses this coal type for power generation. In Ontario, bituminous
coal is imported from coalfields in the Appalachian area of the
United States and is shipped across the Great Lakes for use by three
large generating stations (and also for use in steel production).
All of the coal produced in Nova Scotia, and New Brunswick is bituminous
coal used by electrical generating stations.
Subbituminous coal is found under much of the plains area of Alberta.
Open-pit mines and adjacent generating stations have been built
in places where seams of this coal outcrop at the surface.
Lignite is mined in southern Saskatchewan and used for a number
of electric generation plants close to the mines. Lignite is also
shipped by rail to two generating stations in southern Manitoba
and two in northwestern Ontario.
Refined Petroleum Products
Refined Petroleum Products are the various products created from
refining petroleum. The main ones used for electricity generation
plants are heavy fuel oil, light fuel oil and diesel fuel. Each
differs in the type of plant in which it is used: heavy fuel oil
is used almost exclusively in steam plants, light fuel oil is only
used in combustion turbine plants, and diesel fuel is used in nearly
all of Canada's internal combustion generating stations, as well
as in some large combustion turbine plants. There are two steam
plants using other petroleum products. One, in Alberta uses petroleum
coke, and the other, in New Brunswick, uses an imported petroleum
product called orimulsion.
Natural Gas
In 1997, the main producing provinces for natural gas were Alberta
and British Columbia. Natural gas needs comparatively little refining
- once cleaned of sulphur and natural gas liquids, it can be readily
used wherever pipelines take it. Because there is a dense network
of transmission and distribution lines in Canada, electrical plant
operators have a lot of freedom on where to build gas-fired plants.
Natural gas has advantages over other fossil fuels such as coal
and petroleum products in that gas burns cleanly, thus producing
no acid pollutants. This advantage has made natural gas an attractive
option for future electrical generating capacity.
Nuclear Energy
Canada is a major producer of uranium, which is the fuel used for
nuclear plants. In Canada, all nuclear plants all make use of the
CANDU process which uses natural uranium as the fuel.
Nuclear plants are essentially steam plants: both use a process
to take the heat of the fuel to turn water to steam which then powers
the generators. However, because of the unique nature of both the
fuel and the elaborate plant structures needed to handle it safely,
nuclear plants are usually considered as a separate class of generating
station.
Hydro-electricity
Hydro-electricity is produced by using the potential energy of
water, which usually means tapping the fall of water in rivers so
that it will turn turbines to generate electric power. Canada is
unusually well provided with hydro sites as the country not only
has many rivers, but also the geology of Canada makes it relatively
easy to build the dams and reservoirs needed to exploit hydro potential.
Much of the history of electrical facilities development in Canada
is that of developing hydro sites, so a brief summary will explain
many of the patterns shown on this layer. Electrical power's usefulness
for lighting, and then for industry was demonstrated in the late
19th century. Around 1900, it became feasible to transmit power
from generating sites to nearby cities. As a result, hydro sites
close to centres of population were developed. At first, many of
these were small municipal units built in diverse parts of Canada.
Somewhat later, the level of government authorized to develop resources
in Canada (the provinces) authorized private firms to develop power
sites or created a crown corporation to do this. In most provinces,
the government created a province-wide utility to do this work since
its activities could be better tailored to aid in provincial economic
development.
The size of hydro plants steadily grew: from mainly under 5000
kilowatts in 1900, to 400 000 kilowatts for the Niagara plant of
1928 (now Sir Adam Beck #1), to the Churchill Falls plant of 5 500
000 kilowatts in 1971. Early developments were usually fairly close
to their markets as the development of remote hydro sites had to
await improvements in long-range transmission so that power losses
in transmission would be acceptable. By 1945, hydro reached its
highest proportion of total Canadian capacity (94%). Subsequently,
this percentage has fallen to 60% due to most feasible hydro sites
having been already developed. As a result, from the 1950s on, new
capacity have been roughly equally split amongst thermal, nuclear
and hydro-electric.
There is also a hydro-electric plant in Nova Scotia which uses
tidal energy as its source of power.
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