Renewable Energy for Water Supply Mr Paul Harris Outline • • • • • Introduction Wind Energy Solar Power Comparison with other renewable energy options Conclusions Introduction • Will look mainly at solar and wind energy, as I think they are probably most relevant to most of you. • Happy to try and take questions during the presentation. Wind Energy • Regional and temporal variability – need storage or backup • Pumping, milling or electricity generation • Energy payback a few months • Compatible with other land uses • 13 W per square metre at 10 kph wind speed maximum input energy Slide 7 http://climatelab.org http://www.varcoewindmills.com.au/ Wind Mills • Low speed, high torque • Piston Pump pulsates http://www.varcoewindmills.com.au/ Wind Turbines • High Speed, low torque • Suit helical rotor http://climatelab.org Other Turbines • Savonius vertical axis wind turbine http://www.pcon‐wind.de/ • Darrieus Wind Turbine http://www.reuk.co.uk Wind and Sunshine Solar Energy http://typesofrenewable‐energy.com • Original source of all energy (except geothermal and nuclear) • Generate heat and/or electricity • Influenced by time of day, cloud and season – need storage/backup • Photovoltaics have ~ 5 year energy payback but nasty industrial processes • 1 kW per square metre maximum incoming energy • Alignment of collector is also a factor Slide 12 http://www.solahart.com Solar Distillation • Use the sun’s heat directly http://www.cleardomesolar.com/ Comparison of Technologies To generate 1 kW of electricity “continuously” (to lift 7.5 KL per hour of water 14 m vertically OR push the same flow horizontally through 400 m of 50 mm pipe) you need :‐ • 100 square metres of solar panels and 100kWhr Battery Bank • 90 m2 wind generator (2.2 kW) and 100kWhr Battery Bank (but very little land!) • 860000 m3 storage (12 Ha 14 m deep) and 5000 Ha catchment (Eden Valley) with 10 m drop for micro‐hydro electricity. • About 17 Ha of oil crop for biodiesel • About 7 Ha of maize for bioethanol production • About 10 Ha of 30 y/o woodlot to run a gasifier (Adelaide Hills) • 13 dairy cattle (housed – about 40 Ha of land) and a 110 m3 digester to make biogas Slide 14 Summary Conclusions • Powering a RO unit or pump by solar voltaic panels may be the best option (as solar availability is closely related to stock water demand) • You will need a bigger RO unit or pump if you don’t have battery storage. • Look at your own situation, an unusual combination may provide an optimum solution. Thankyou! Any Questions?