heat absorbing

/ˈhiːt əbˌzɔːrbɪŋ/
adjective
  1. Designed or able to take in and hold heat from the surroundings.
    • The heat-absorbing glass on the windows helps keep the building cool in summer.
    • A dark, heat-absorbing roof can make the house warmer in winter.
    • Solar panels use heat-absorbing materials to capture energy from the sun.