It is known, from Meteorological Office Records, that in the United Kingdom, we can expect to "enjoy" 1, 500 hours of bright sunshine every single year. Enjoyable, that is, if you are simply planning to have a break from the office and do your own thing - not so, if you are tied to your desk trying to do a job of work. Taking London (at 51.7 North) as an easily located example, the potential heat gain through vertical glazing is comparable to that experienced in the Middle East. During Spring and Autumn, they are much on a par and during peak summer months, London is exposed to a full 35% additional solar energy than say Jeddah or Riyadh. The challenge is simple but equally daunting when you accept the fact that every 1.4m of glazing can effectively transmit heat at the same rate as a 1 kW single bar electric fire. The cost of removing that heat in terms of air conditioning can be staggering and the dual problems of direct radiation and glare still persist.