1. Introduction to Solar Distillation of Water
Fritz R. Fiedler

2. Basic Configuration

3. Computations Mass Balance: water Energy Balance: heat
Control Volume concept

4. Mass Balance: VariablesQC QI QO

5. Mass Balance control volume: still boundary time period: 1 day
inflow (M) = outflow (M)
QI(M/T)*t(T) = QO(M/T)*t(T) + QC(M/T)*t(T)
QI(kg/d)*t(d) = QO(kg/d)*t(d) + QC(kg/d)*t(d)
for “batch” type still, QO = 0
1 L ÷ (1000 L/m3) * (1000 kg/m3) = 1 kg
other losses??

6. Heat Balance
Complicated! Must account for reflected, absorbed, transmitted radiation as a function of material types
The effective energy, QE, is the amount that goes directly into obtaining some mass of purified water, ME
ME(kg/m2•d)=QE(Joules/m2•d)/L(Joules/kg)

7. Latent Heat of Vaporization
energy required to change the state of water from liquid to vapor (overcome forces of molecular attraction)
at 100°C, L = 2.26x106 Joules/kg
at 0°C, L = 2.5x106 Joules/kg

8. Still Efficiency Let QT be total incoming solar radiation
efficiency = h = QE / QT
Where will we obtain QE?
Where will we obtain QT?

9. Typical Climate Station

10. UI Plant Science Farm

11. Radiation Data Units of watts/m2 15 minute averages 1 watt•s = 1 Joule
1 watt•15 min = 900 Joules
so to get total Joules/day, sum 15 minute averages, multiply by number of 15 minute intervals per day (96), multiply by 900 sec per 15 minutes

12. Climate Variability
How representative are the data collected at the UI Plant Science Farm climate station of conditions on the roof of BEL?
user name: iu password: moscow
data from climate stations set up to monitor road conditions: Paradise Ridge, Snow Road, Reisenauer Hill

13. Climate Variability
10:50 am

14. Data?
What data are required to perform mass balance (and estimate losses)?
What data are required to determine still efficiency?
Develop a measurement and data collection plan!