Today, we have a guest post by Philip Piletic. I hope you find the post as fascinating as I found it. I love learning about the new technologies that will become more prevalant as we continue down the path of sustainability.
America’s energy future lies in a revolution of green technology. Advances in solar and geothermal power are among the tools needed to achieve energy independence. Unconventional new processes like cellulosic ethanol production and generating power using microbes are potential contributors to decreasing imports of fossil fuels. These developments represent opportunities for manufacturers of valves, actuators and controls, as well as employment opportunities for engineers and construction and maintenance workers.
Cellulosic Ethanol Many argue that the amount of water required to grow the corn and the fossil fuels needed to operate the machinery to plant and harvest it cancel out the carbon reduction of using ethanol. Further, they argue that less corn is available for both human consumption and cattle feed.
Up until now, ethanol production has always utilized corn starch. In June of 2014, the first commercial facility for producing cellulosic ethanol was opened. The Quad County Corn Processors plant in Galva, Iowa has produced the first ethanol made from corn kernel fiber. Utilizing the raw material left in cornfields after harvesting and the waste generated by ethanol production in the bio-refinery that has been operating since 2000, they’ve taken recycling to a whole new level.
As part of the Biomass Research and Development Initiative, the technology was developed using a $4.25 million dollar investment from the USDA and the Department of Energy. After four years of research and development, ethanol has successfully been produced using corn fibers. That success led to further research into the possibility of transforming corn leaves and stalks, wood scraps and even garbage into ethanol. Two companies, DuPont Danisco and Poet-DSM, are building cellulosic ethanol plants at a cost of $225 million and $250 million respectively. Both are utilizing ethanol plants already in existence and will use corncobs and husks from local farmer’s fields to make cellulosic ethanol.
Green Construction Efficient HVAC and waste and water recycling systems are two areas of green construction that require state-of-the-art technology to achieve the highest possible degree of energy savings. One of the most impressive projects utilizing green construction is a residential subdivision in Canada. The Drake Landing Solar Community in Okotoks, Alberta, is the only facility of its kind in the world. It incorporates a gutter-and-barrel system that saves rainwater, and was built with sustainably harvested lumber and recycled drywall and insulation. The result is that the homes are 30% more energy efficient than standard homes.
The heating system, a borehole thermal energy storage (BTES) is the most impressive technological feat, though. It’s an underground structure that stores heat collected by a system of 800 flat plate solar panels mounted in four rows on the homes’ detached garages. When the sun shines, a solution of water and non-toxic glycol is heated by being pumped through the solar collectors. The collectors are connected by an insulated underground pipe that carries the heated solution to the community energy center.
The BTES consists of an array of 144 boreholes at a depth of 121 feet (37 metres) into which U-shaped pipes are inserted and filled with a high thermal conductivity material. The units are arranged in a grid with 7.4 feet (2.25 meters) between them. The U-pipes are joined together in groups of six, and all connect back to the energy center building. After covering the 114 feet (35 metres) BTES field with a layer of insulation and soil, a landscaped park was built on top. Heated water passes to the short-term storage tank in the energy center where all the pumps and control valves are located, then circulated to the homes, supplying 90% of the community’s heating needs, even during the winter.
Geothermal Power Projects According to the Geothermal Energy Association’s 2014 Annual U.S. & Global Geothermal Power Production Report there were almost 700 projects under development in 76 countries. Only 85 MW of new geothermal capacity out of 530 MW were in the U.S. Stagnation in the U.S. market was attributed to policy barriers, low natural gas prices and inadequate transmission infrastructure.
GEA Executive Director Karl Gawell thinks there is untapped potential for geothermal energy and opportunities for site development. The geothermal industry is working towards 977 MW of new capacity at current sites in eight western states, including Utah, Nevada, California and New Mexico. The Salton Sea Resource Area has more geothermal generating capacity than anywhere else in the U.S. The Imperial Irrigation District has pledged to build up to 1,700 MW of geothermal energy there by the early 2030’s. It’s estimated that due to the isolation of the area, it would take 150 miles of transmission line to carry the power to the rest of the state. Despite the initial investment, the recent closure of two power plants in the region, combined with the clean sustainability of geothermal power, makes it a good long-term alternative.
Bug Power Engineers at Stanford have invented a new way to generate electricity by using microbes found in sewage that produce electricity during the process of digestion. Scientists have been able to capture this electricity using a battery with two electrodes and a bottle of waste-water. The microbes, a type of bacteria that feeds on organic waste, are attached to the negative electrode and produce electricity that is captured by the positive electrode. Although more research is needed before this method can become economically viable, one day it will be possible for bacteria to provide enough energy to partially power a sewage or wastewater plant.
The Future California’s desalination project using solar energy is one solution to agricultural drought, but the brine created by the process is considered hazardous waste. In the future, the whole lifecycle of a project or process will be considered before it can be called “green”.