194
Enhanced geothermal systems for clean firm energy generation | Nature Reviews Clean Technology
www.nature.comGeothermal energy provides clean, steady and renewable electricity and heat, but the use of geothermal energy has conventionally been constrained to locations with adequate subsurface heat and fluid flow. Enhanced geothermal systems (EGS) enable geothermal energy usage in unconventional areas by enhancing the subsurface permeability and increasing fluid flow, which is then extracted as a carrier of the thermal energy. In this Review, we discuss the development of EGS and its role in providing energy. Some EGS are operating commercially in Europe and provide heat and/or electricity, but technical issues and concerns over induced seismicity have historically hindered the broader expansion of EGS. Adaptation of advanced drilling techniques (including the use of polycrystalline diamond compact bits, multiwell drilling pads, horizontal drilling and multistage stimulation) is enabling an increase in scale and decrease in cost of EGS projects. As a result, in the USA, enhanced geothermal is expected to achieve plant capital costs (US$4,500 kW−1) and a levelized cost of electricity (US$80 MWh−1) that are competitive with market electricity prices by 2027. With further development of EGS to manage induced seismicity risk and increase system flexibility, EGS could provide stable baseload and potentially dispatchable electricity in clean energy systems. Enhanced geothermal systems can provide clean energy in areas where conventional geothermal systems are not viable. This Review discusses energy production through these systems and the technological developments that could enable its future expansion.
AFAIK, the number of protons and neutrons is the same, but the overall mass is reduced because the binding energy holding the nucleus together counts towards the mass. I do not understand why the binding energy acts as mass (I dropped out of physics after moving past classical mechanics), but that’s what’s I’ve heard over the years.
So basically, you have it right, and my explanation is overly simplified because I am not very competent and forgot how this shit worked lol. I remembered that the overall mass of the waste is lower than what was put in, but I fucked up when explaining why that happens. Breeder reactors can’t do much with the fission products themselves, but the worst part of nuclear waste from a long-term storage perspective is the transuranics that get created inside of a reactor. FBRs make a lot of neutrons that can transmute those transuranics into fissile materials and then burn them up, extracting the binding energy from them and reducing the overall mass. Eventually you’re just left with fission products which are generally very short lived.
EDIT: I accidentally hit post way too soon, so I wrote most of this as an edit. Apologies for that.