Sudoku is a logic-based placement puzzle consisting of a 9x9 grid of cells. Typically using numbers, this puzzle uses energy source symbols for biomass, coal, geothermal, hydropower, natural gas, petroleum, solar, uranium and wind.
To solve the puzzle, each 3x3 region of the grid must contain only one source symbol. Each row and each column of the puzzle must contain only one energy source symbol. There is only one solution. Good luck!