Fill in the Blanks WHAT WILL YOUR GENERATION DO?Online version Fill in the blanks by Mª Coronada Toro Gordillo 1 non fuel renewable biomass coal solar two Types of energy There are main types of energy resources . These are renewable and - energy sources . Renewable energy sources are those which will not run out and can be used over again . These include wind , tidal and energy . Non - renewable energy sources can only be used once . They take millions of years to form e . g . oil , and natural gas . Some resources are thought to be both renewable and non - renewable . These are : wood - when wood is used for fuel and replanted it is a form of renewable energy . - changing farming wastes , grasses , trees , bark , sawdust , and other things into energy by burning it , changing it to a gas , or converting it to a liquid .