The alternative energy sector is the best performing sector for the third consecutive day, as the problems in Japan continue to have a positive effect on shares. The sector has risen almost 14% over the last week.Workers had to be evacuated from the stricken Fukushima Dai-ichi nuclear plant after a fire at reactor No.4 sent radiation levels soaring. Plant operator Tokyo Electric Power (Tepco) told staff to move away from the reactors inside the plant after radiation levels jumped at around 10am Japan time. Fears of a disaster reminiscent of the Chernobyl nuclear accident of 1986 has hit confidence in nuclear and power stocks, and boosted optimism for renewable energy companies. Fuel cells and micro-CHP products developer Ceramic Fuel Cells and wind turbine gearbox manufacturer Hansen Transmissions are among the high risers.Banks are on the decline, led by HSBC and Standard Chartered, who have both closed all their branches in Bahrain because of the unrest in the Middle East state.Barclays and Lloyds are also lower.Top performing sectors so far todayAlternative Energy 3,274.84 +4.86%Electricity 7,442.00 +1.26%Industrial Metals & Mining 7,483.46 +1.03%Construction & Materials 4,089.18 +0.49%Food Producers & Processors 4,813.16 +0.38%Bottom performing sectors so far todayBanks 4,555.96 -2.68%Automobiles & Parts 4,334.77 -2.27%Mobile Telecommunications 3,832.51 -2.14%Life Insurance 4,217.66 -2.03%Fixed Line Telecommunications 2,255.60 -2.02%