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  reprint (by W. Scharnhorst ) Divestment of stocks in fossil fuel companies may seem like a good idea if the goal is to put financial pressure on conventional energy companies and thereby leave an opening for cleaner alternative fuels in the fight against climate change. The question is whether the strategy works. Certainly any company, whose core business is making money, is likely to take notice of any activity that affects its revenues. Yet many argue that a drop in investment in an energy company may not be the best way to get its attention, especially at a time when alternative energies are scarce and fossil fuels remain the dominant source of power . In other words, how many people today can afford to junk their gasoline-powered cars and invest in more expensive electric models? That’s exactly the point made by London Mayor Boris Johnson, a member of Britain’s Conservative Party who also harbors libertarian, if not liberal, political views. The Lond...

-- a _kt75 | reprint Download: Quarterly Notes on Sustainable Water Management - Q01/2014 There is a boom in renewable energy sources coming online worldwide, but the predominant types – solar and wind – are problematic due to their variable nature. For most regions of the world, the sun cannot be expected to shine nor the wind blow when required. What is needed is a way to capture that energy when available, perhaps in the middle of the night, when demand is low, and then store it until it can be used when demand rises. But this is not a trivial problem to solve. _progress | M replaces _kt75 | mirror. visit: http://progress-m.blogspot.com . ready: 01.07.2015. close ✕ According to the European Wind Energy Association , at the end of 2013, the UK had 10.5GW of wind turbine capacity installed, with more in planning and construction. As the percentage of energy generated from renewables increases, the intermittency problem becomes more acute, as has been ...

-- a _kt75 | reprint Download: Quarterly Notes on Sustainable Water Management - Q01/2014 When Ergon Energy began a Solar Cities program on Magnetic Island to try to make the isolated community as efficient and self sustaining as possible – and avoid an expensive new cable to the mainland grid – one of the first things it did was to remove all the old bar fridges. It filled up more than a shipping container and took them off the island. Bar fridges, explains Ergon Energy CEO Ian McLeod, are usually old, and terribly inefficient. Roofs on the island were also painted white to dissipate the effects of the sun’s heat on household interiors. Solar was installed and the new cable deferred for nearly a decade. Now, with storage about to be installed on Magnetic Island, the new cable will probably never be needed. This is now becoming the model for regional and isolated communities around Australia . Inefficient appliances like old bar fridges are being replaced, local gene...

► NEW : see all _kt75 | articles at a glance in the _news database   -- a _kt75 | reprint   Tweet _progress | M replaces _kt75 | mirror. visit: http://progress-m.blogspot.com . ready: 01.07.2015. close ✕ The year 2012 was another historic one for solar photovoltaic (PV) technology, which has experienced remarkable growth over the past decade and is on the way to becoming a mature and mainstream source of electricity. The world’s cumulative PV capacity surpassed the impressive 100-gigawatt (GW) installed electrical power mark, achieving just over 102 GW. This capacity is capable of producing as much annual electrical energy as 16 coal power plants or nuclear reactors of 1 GW each. Each year these PV installations save more than 53 million tons of CO2. Remarkably, even during a time of economic crisis, an estimated 31 GW of new PV capacity was commissioned around the world in 2012 – roughly the same as in the record-setting year of 2011. But even if the he...

-- a _kt75 | reprint   Tweet   Renewable energy sources, at least wind and solar, are variable — the wind isn’t always blowing, the sun isn’t always shining. This is something every glib pundit on the internet cites as a reason we’ll need fossil-fuel or nuclear “baseload” power plants for the foreseeable future. It’s a frustrating topic, since people who actually study the subject (like NREL) have shown that there are all sorts of ways to handle variability without disrupting the grid. One of those ways is transmission : building power lines to take renewable energy from where it is abundant (often remote areas) to where it is needed (mainly big cities). More specifically, the idea is to build high-voltage direct-current (HVDC) lines that would carry energy over long distances from remote sites and feed it into the alternating-current (AC) lines that serve urban areas. (The DC vs. AC question is interesting, but not particularly essential...