Glass materials are essential in everyone’s life by enabling daylight to reach the interior of our buildings, being the primary component for communication via optical fibers and a key component in electronic devices as protective cover and/or dielectric material. It is also an essential component in solar energy applications which comprise, e.g., photovoltaics , solar thermal collectors, greenhouses and algae reactors, by acting as a protective and light transmitting barrier. Glass as a cover material for solar energy applications constitutes a significant part of the costs and is an important component for efficient light capture and protection to the environment. The research and development of cover glass for solar energy applications have so far received limited attention even though it is an important material for our future sustainable development. Recent research efforts have provided knowledge of which properties that needs to be optimized - balancing efficiency, service lifetime and cost. The challenges of cover glass for different solar energy applications differs somewhat but all have in common the efficient solar light capture and protection to the environment. Thus, the know-how can be used in several different industrial sectors. The fundamentals of cover glasses for solar energy applications as well as previous and on-going project concepts will be presented. This includes i) state-of-the-art of cover materials for greenhouses, ii) results on optimization of cover glass for photovoltaics , iii) initial results on how to provide both anti-reflective and anti-soiling properties, iv) results on broadband antireflective coatings for solar thermal energy, and v) other promising concepts. At last will some future challenges and needs be discussed, e.g., in relation to the concept of ideal material choices for PV.