Solar thermal ‘concentrating’ power stations (CSP) can only use direct sunlight and are therefore dependent on very sunny locations. North Africa, for example, has a technical potential for this technology which far exceeds regional demand. The various solar thermal technologies (detailed in Chapter 9) have good prospects for further development and cost reductions. Because of their more simple design, ‘Fresnel’ collectors are considered as an option for additional cost trimming. The efficiency of central receiver systems can be increased by producing compressed air at a temperature of up to 1,000°C, which is then used to run a combined gas and steam turbine.

Depending on the level of irradiation and mode of operation, it is expected that long term future electricity generation costs of $ 6-10 cents/kWh can be achieved. This presupposes rapid market introduction in the next few years. CSP investment costs assumed for this study and shown in table 4.7 include costs for an increasing storage capacity up to 12 hours per day and additional solar fields up to solar multiple 3, achieving a maximum of 6,500 full load hours per year.