More on mercury
More on mercury
Although all fossil fuels contain mercury, the amounts vary considerably. The highest content is found in low-quality lignite, which contains about twenty-times as much mercury as natural gas. Previously (Mercury: A Broader Perspective, IAEEL Newsletter 3/93), we compared the amounts of mercury released to the environment per million lumen-hours for compact fluorescent lamps and incandescent lamps.
CFLs were assumed to contain about 5 mg of mercury, and incandescents none. A comparison of CFLs and incandescent lamps based on the US electrical generating mix revealed that the overall release of mercury from discarded lamps and power generation was more than twice as high in connection with the operation of incandescent lamps.
Of course, each country (and utility) is different: In the diagram, the situation in 18 western European countries is represented alongside the US. Shown above each bar is the percentage reduction in mercury that can be realized by converting from incandescents to CFLs.
Reductions range from 12% (France) to 67% (Denmark), depending on the kinds of fossil fuels used to generate electricity. In five of the countries (Luxembourg, Iceland, Norway, Sweden, and Switzerland) there are not enough fossil fuels in the production of electricity to offset the mercury contained in a CFL. In these countries, hydroelectric and nuclear power dominate.
In fact, potential mercury releases are associated with each of these technologies ("natural" mercury from rotting vegetation in areas flooded for hydropower and mercury mobilized in the mining of uranium), but there are no readily available estimates of the exact amounts.
See also:
Mercury and Lighting: Managing the Problem, IAEEL 3/93)
Mercury: a Broader Perspective (IAEEL 3/93)
Drastic cut in mercury (on low-mercury HPS lamps; IAEEL 3/94)
Mercury-cut increases efficiency (0n reduced Mercury fluorescent lamps, IAEEL 4/94)
New HPS lamp not in Europe (IAEEL 1/95)
0% mercury retrofit HPS (IAEEL 1/95)
Evan Mills
| Comparisons based on one million lumen hours provided by a 60-W incandescent lamp versus a 15-W CFL. Reductions (shown above the bars) reflect the combined lamp- and electricity-related amounts of mercury. Values for the mercury content of fuels are drawn from the detailed analysis performed by Bob Clear, Lawrence Berkeley Laboratory. |