It is not too different from the potential panic caused by a dirty bomb (A bomb, contaminated by radioactive substance such as Cesium-60). The real problem would most likely be the massive public panic and outcry, rather than the very slightly increased cancer rates.
Basically every way of generating electricity, except solar power cells, involve spinning a generator to generate electricity. Even large solar installation do that by heating a fluid and running it through a generator. The most efficient generator use a combined cycle where gas are run through at the high temperature and then used to boil water for a stream turbine.
http://en.wikipedia.org/wiki/Gas_turbine#Industrial_gas_turbines_for_power_generation