The Solar Tower 1.Principles of operation 2.Carbon cost of manufacture 3.$$ cost and carbon credits By Dr Timothy W. Schmidt University of Sydney AUSTRALIA

1. Principles of operation Solar radiation Hot air Wind turbines 1000m

1. Principles of operation Glass panels trap heated air – the real greenhouse effect! 50°C typical. Peak flux averaged over 24h Peak flux (instant equilibration)

1. Principles of operation Assume T const Heavy air column Light air column

1. Principles of operation Kinetic energy in air mass   v 2 =4MW 120m Designers say 200MW This requires the air in the base of the tower to be moving at 221m/s… unless I am mistaken. problem the real air flow in this chimney is 10 to 15 m/s a pressure gap exists between upstream and downstream the turbine. The theoretical power output (before subtracting various losses) is equal to this pressure gap multiplied by the voluminal air flow, in m³/s. This pressure gap calculates as in the hydrostatic problem, by integrating, over the whole chimney height, the voluminal weight difference between outside and inside the chimney.

2. Carbon cost of manufacture Glass panels! 20,000,000 m 2 100,000 kg 1.3 TJ OK – only 2h of operation Source: 5g/m² ratio for the glass cover seem underestimated => more then 2h

2. Carbon cost of manufacture Tower 1,000 m 2,000,000 m 3 concrete 4.6 Tg 26 PJ 8 years of power OK Source: In reinforced concrete only two components are CO2 unfriendly: the steel reinforcement, and the cement powder. The others (sand, pebbles, water) have no carbon cost. => "8 years" is overestimated.

3. $ cost Tower cost estimated at 170 M€ 2,000,000 m 3 concrete = 30M€ Add labour – plausible Glass $10/m 2 $200M = 140M € Add labour – plausible

3. $ cost 200 MW power station 680 GWh/a We get 905 kWh/tonne CO2 Abate 750,000 tonnes CO2/a Can sell for 20 € 15M€ pa