Daily Archives: September 17, 2015

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. 


Source: Wattsupwiththat.com

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.

POU Reverse Osmosis Units Require Careful, On-Going Maintenance

Sacchetti R, De Luca G, Guberti E, Zanetti F. Quality of Drinking Water Treated at Point of Use in Residential Healthcare Facilities for the Elderly. International Journal of Environmental Research and Public Health. 2015 Sep 9;12(9):11163-77. doi: 10.3390/ijerph120911163.

Municipal tap water is increasingly treated at the point of use (POU) to improve the acceptability and palatability of its taste. The aim of this study was to assess the bacteriologic and nutritional characteristics of tap water treated at the point of use in residential healthcare facilities for the elderly. Two types of POU devices were used: microfiltered water dispensers (MWDs) and reverse-osmosis water dispensers (ROWDs). All samples of water entering the devices and leaving them were tested for the bacteriological parameters set by Italian regulations for drinking water and for opportunistic pathogens associated with various infections in healthcare settings; in addition, the degree of mineralization of the water was assessed. The results revealed widespread bacterial contamination in the POU treatment devices, particularly from potentially pathogenic species. As expected, the use of ROWDs led to a decrease in the saline content of the water. In conclusion, the use of POU treatment in healthcare facilities for the elderly can be considered advisable only if the devices are constantly and carefully maintained.