Renew Extra Weekly

An intriguing   US study   looks to looks to getting rid of hydro dams, and at compensatory ‘solar-power replacement as a solution for hydropower foregone in US dam removals’ . It notes that ‘there is a growing dam removal movement in the United States, driven in part by environmental, safety and cost considerations. These include electricity-producing hydro-dams, many of which are ageing and will require substantial maintenance or removal over the coming decades’ .   And it looks to solar PV to replace the lost power.   According to Dr John Waldman, an aquatic conservation biologist from the City University of New York who led the study, many environmentalists have come to see dams as ‘blood clots in our watersheds’ owing to the ‘tremendous harm’ they have done to ecosystems.   Carbon Brief quotes him as as saying that the ‘poster children’ for this effect are migratory fish, such as salmon and shad, whose numbers have declined by several o...

Covid 19 may have undermined the global economy and that may impose some temporary   constraints on the growth of renewables , but longer term, as costs continue to fall for most of the renewables, the future looks very good. As my last three posts should have indicted, solar energy is doing well, both for heat, at 470GWth, and for power, with photovoltaics now at over 580 GW globally.   The cost of solar PV has fallen by some 90% over the last 10 years, and further reductions are expected . Power from large ground mounted utility-scale systems, which Lazarus put at $32- 42/MWh, is significantly cheaper (typically four times cheaper ) than that from domestic-scale roof top units, given commercial economies of scale, but the later boomed when the Feed In Tariff (FiTs) system adopted across much of the EU, made ‘self-generation’ by ‘prosumers’ economically attractive.   However, the FiT scheme has been replaced in most countries with competitive tendering arrangements ...