The proportion of electricity produced in WA's main power grid from coal has jumped more than 30 per cent in seven years despite carbon pricing and concerns about climate change.
New figures from the body that runs the wholesale electricity market in the South West reveal that coal has well and truly overtaken gas as the dominant fuel source.
In its annual snapshot, the Independent Market Operator noted coal as a fuel accounted for about half of all electricity produced last year.
The total energy produced by coal-fired power stations had risen 33 per cent since 2007, the IMO found.
In contrast, cleaner-burning natural gas fell as a source of fuel for electricity generation by 8 per cent over the same period and now accounts for about 40 per cent of production.
Renewable energy sources such as wind turbines and solar farms almost doubled their output, though they still only represented 9 per cent of generation last year.
The IMO figures highlight the vital nature of coal-fired generation to the State's economy, particularly in the South West where surging gas prices have made coal more affordable.
They also underscore the risks associated with continuing financial troubles at WA's two major coal mines.
Energy Minister Mike Nahan has expressed concern over the plight of Indian-owned Griffin Coal and Chinese- controlled Premier Coal.
The two Collie mines supply coal to plants run by privately-owned Bluewaters and State-backed Synergy that collectively represent almost all WA coal-fired power production.
Dr Nahan has said coal will continue to be vital to power production in the South West because it is by far the most affordable source.
Shadow energy minister Bill Johnston said last year's increase in coal-fired generation could be explained by the reintroduction of Muja AB, the 60-year-old power plant controversially refurbished by the Government.
Mr Johnston said though coal had become more affordable in light of higher gas prices, its price, too, was set to rise.