燃やす
abstract
alternative
background
biomass
brown
chip
chips
closeup
conservation
eco
ecology
economy
energy
fiber
fire
flame
fuel
green
heat
heating
hot
industry
many
mass
material
natural
nature
nobody
object
pattern
pellet
pellets
power
raw
renewable
roll
solid
source
stove
structure
texture
textured
timber
tree
winter
wood
wooden
working