Ground-up walnut shells that could not be used for their usual purpose because they got wet in the May tornadoes are becoming a renewable fuel for a mid-Missouri electrical cooperative. Central Electric Power Cooperative is mixing one part walnut shells with nine parts of coal. Manager Don Shaw says it works well, even if it is just a one-time deal. Shaw says three-thousand tons of water-damaged ground walnut shells are being fed into the boilers at the Chamois power plant. The co-op also has experimented with chipped tires and chelled corn.