by: Michael Hoexter
I realize I overlooked in my last post some technologies that will also play a major role in cutting our GHG emissions. This is an oversight on my part. I am not claiming that these 4 additional technologies will lead to more overall GHG reductions if we fully deploy the 20 listed in the first post (I arrived at a figure of approximately 93.7% reductions over 2000 emissions) but they deepen the choices and reiterate the contention of many in the anti-global warming movement that exploratory research is nice but not necessary to cut emissions substantially. More importantly, technologies already exist or will emerge, so the original list is not meant to be exhaustive or final.
Geothermal electric power – “Heat farming” from the heat of earth’s crust and mantle. Currently geothermal electric power is restricted to certain hot zones such as Iceland, parts of the western US, Italy and Australia, but an emerging technology called EGS (enhanced geothermal systems) which drills holes deep into the the heat of the lower bedrock will allow geothermal to extend its range to almost any location on earth. Advocates of EGS are asking for $1 billion of research into this technology but additionally, regulatory incentives will drive drillers, currently concentrating on oil drilling to participate with EGS plant developers. (>4% GHG reduction)
Hydroelectricity/Pumped Storage – While the building of hydroelectric dams played a key role in galvanizing the early environmental movement and still provoke strong pro and con feelings, the emergence of global warming as one of the main concerns for the well being of planetary eco-systems has raised the profile of hydroelectricity. Some are unwilling to consider hydroelectricity at all as an option but this fundamentalist position must be reconsidered in light of newer technologies that are more conservative of river environments. Existing dams without hydroelectric facilities can be made productive of power, while new small and medium size dams can be constructed in ways that interfere much less than traditional large hydroelectric dams. Hydroelectricity is one of the higher quality sources of electricity and can integrate well with intermittent renewables. Pumped storage is one of the key storage media other than CSP with thermal storage that can balance energy production with energy demand. (>5% GHG reduction)
Ground Source Heat Pumps – Ground source heat pumps are an existing technology that cut heating and cooling costs by 60 to 75%. Expensive as a retrofit, the additional cost of trenching or bore holes can be reduced when installed with the foundation during new construction. (>6% GHG reduction)
High Voltage Transmission – A much overlooked and sometimes hated part of our landscape, the direct current version (HVDC/HVAC) is a more compact, more environmentally friendly, and more efficient version. No GHG emissions are directly attributable to HVDC/HVAC but transmission will allow widely dispersed renewable electricity generators to coordinate and supply electric demand. Transmission allows the most of the top renewable generators to serve electricity demand. (enables >59% GHG reduction with renewable generators)
These can all be described as existing or emerging. However, the EGS system still requires a good deal of rather capital intensive development, so EGS gives partial support to the contention of the “Dangerous Assumptions” authors that research is required for carbon neutral technologies to become available, however it also highlights the need for a market incentive to drive the development and deployment of that particular technology. A temporary premium price per kWh for an EGS plant would, for instance, array market forces behind the development and eventual deployment of EGS plants. This is however, among the 24 technologies in this list one of the few in which R&D is a pre-requisite to deployment.