燃やす
alternative
background
bio
biomass
block
brick
briquet
briquette
brown
compressed
conservation
consumption
development
dry
eco
ecological
ecology
economy
energy
environment
environmental
firewood
forest
fuel
heap
heat
industry
manufactured
mass
material
natural
nature
packaged
pellet
pile
power
recycling
renewable
roll
sawdust
stove
sustainable
timber
white background
wood
wooden