Category Archives: Renewable Energy

World’s largest solar panel farm requires 200,000 liters of good quality water each day.

“It takes as much as 2 lakh litres of good quality water to keep its 25 lakh solar modules clean each day. That water is sourced from borewells 5 km away without permission from the district authorities, the villagers allege.” click here

Industrial wind turbines cause adverse health effects

“Research has demonstrated how various forms of pollutant from IWTs can adversely affect human health. These include noise, infra-sound, dirty electricity, and ground current which can each, along with shadow flicker, contribute to ill-health among those who live near wind turbines.” click here

Solar Powered NF/RO Systems, Tanzania

Owusu-Agyeman I, Shen J, Schäfer AI. Renewable energy powered membrane technology: Impact of pH and ionic strength on fluoride and natural organic matter removal. The Science of the total environment. 2017 Nov 23;621:138-147. doi: 10.1016/j.scitotenv.2017.11.111.

Real water pH and ionic strength vary greatly, which influences the performance of membrane processes such as nanofiltration (NF) and reverse osmosis (RO). Systematic variation of pH (3-12) and ionic strength (2-10g/L as total dissolved solids (TDS)) was undertaken with a real Tanzanian water to investigate how water quality affects retention mechanisms of fluoride (F) and natural organic matter (NOM). An autonomous solar powered NF/RO system driven by a solar array simulator was supplied with constant power from a generator. An open NF (NF270) and a brackish water RO (BW30) membrane were used. A surface water with a very high F (59.7mg/L) and NOM (110mgC/L) was used. Retention of F by NF270 was <20% at pH<6, increased to 40% at pH6, and 60-70% at pH7-12, indicating a dominance of charge repulsion while being ineffective in meeting the guideline of 1.5mg/L. Increase in ionic strength led to a significant decline in retention of F (from 70 to 50%) and electrical conductivity (from 60 to 10%) by NF270, presumably due to charge screening. In contrast, BW30 retained about 50% of F at pH3, >80% at pH4, and about 99% at pH >5, due to the smaller pore size and hence a more dominant size exclusion. In consequence, only little impact of ionic strength increase was observed for BW30. The concentration of NOM in permeates of both NF270 and BW30 were typically >2mg/L. This was not affected by pH or ionic strength due to the fact that the bulk of NOM was rejected by both membranes through size exclusion. The research is carried out in the context of providing safe drinking water for rural and remote communities where infrastructure is lacking, and water quality varies significantly. While other studies focus on energy fluctuations, this research emphasises on feed water quality that affects system performance and may alter due to a number of environmental factors.

A Carbon Tax will Not Make Renewables More Affordable or Alleviate their Problems

“Imagine for a moment that all the wild claims of climate driven future weather disasters will occur as predicted. In this imaginary future climate dystopia, how will wind power cope with super storms? How will solar power cope with hail, tornadoes, cyclones and floods? How will hydro power cope with endless droughts? How will biofuel crops cope with storm damage, droughts and unseasonal heatwaves?” click here

Renewable Energy Cost Comparison

An informative post here comparing the cost of renewable energy. I purchased my first solar system for my home in the early 1980s. There were tax breaks then (sound familiar) and many promises made that with just a little more research solar, wind, and other renewables will be able to replace fossil fuels. We know now that this is wishful thinking (despite pleas such as this to make it not so). $150 million dollars will not change basic physics, energy conversion, and heat transfer realities. Get over it. Renewable energies depend on coal and other fossil fuels which will always be more cost effective. There’s a need and a place for renewables as well as fossil fuels.

The inefficiency in energy conversion and higher cost of renewables simply cannot be over come. 



PS: I show this presentation by Dr. David McKay  in my Sustainable Civil Engineering class because it provides a good reality check on the feasibility of renewables in the UK.

Environmental Advantages of Renewable Energy Are a Myth?

“Renewables use sun, water, wind; energy sources that won’t run out. Non-renewables come from things like gas, coal and uranium that one day will. But unless electricity and motorised transport are abandoned altogether, all “renewables” need huge areas of land or sea and require raw materials that are drilled, transported, mined, bulldozed and these will run out. Wind turbine towers are constructed from steel manufactured in a blast furnace from mined iron ore and modified coal (coke). Turbine blades are composed of oil-derived resins and glass fibre. The nacelle encloses a magnet containing about one third of a tonne of the rare earth metals, neodymium and dysprosium. Large neodymium magnets also help propel electric cars.” click here

[PS: In case anyone wonders, I am not opposed to renewable energy sources. I am for complete disclosure of information. ]

Membrane Technology Powered by Renewable Energy to Treat Drinking Water

Schäfer AI, Hughes G, Richards BS. Renewable energy powered membrane technology: A leapfrog approach to rural water treatment in developing countries? Renewable and Sustainable Energy Reviews. Dec2014, Vol. 40, p542-556.

Lack of access to safe drinking water remains a present concern in many developing countries, particularly in rural locations. Membrane water treatment technologies have the potential to remove microbiological and chemical contaminants reliably and simultaneously from a wide range of water sources. When powered by renewable energy, these systems are autonomous and have the ability to ‘leapfrog’ over installation of traditional infrastructure for electricity and water supply to reach remote communities. In this paper, current estimated costs for water, membrane plants and infrastructure are compared to indicate the window of opportunity for these exciting renewable energy powered membrane (RE-membrane) technologies. General estimated costs for decentralized membrane systems are within the range of some untreated water costs in developing countries. Specific system costs, however, are very process and location dependent. The appropriateness of a successful approach thus depends partially on careful examination of these parameters. In view of the comparisons made here, the biggest hurdle to adoption of the RE-membrane technology in a remote location may not be cost, but rather sustainability issues such as the lack of skilled personnel for operation and maintenance, service networks, availability of spare parts, socio-economic integration and adaptive capacity of communities to transfer and develop technology appropriate to local needs and circumstances.

Click here for paper (fee).