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In Texas, a new power plant could redefine carbon capture
- OhDagny 8y agoAnother environmental article, another round of crickets from the cognescenti of hacker news. I love that the oil and gas industry pretends that shoving a bunch of CO2 gas in the ground is effective carbon capture. As if gas won't leak out. Hey look! We "captured" it! Sure we're not measuring the entire countryside to see if it gets out some other way... And we'll be sure to plug that hole extra special tight, because we are oil and gas: we dot our Is and cross our Ts and
- mirimir 8y agoThat's a very complicated way to generate electricity from methane. But why do we want to do that? Isn't it better to get our electricity from PV, and reserve methane as a chemical feedstock?
- adventured 8y agoNo. We should very aggressively pursue the use of natural gas until all coal plants are shuttered. Then we move on to dealing with natural gas after that. Anything that makes natural gas better in the meantime, is a plus to the process. China for one example is getting an extraordinary amount of their electricity from coal. They're consuming more coal than the rest of the world combined. You are largely not going to be able to fully replace that with PV in the next 20-30 years. It can potentially be replaced with natural gas, nuclear and a combination of traditional renewables. The US is in the same boat, albeit with a much lower level of coal consumption and a vast domestic supply of natural gas. All coal plants should be shut down in the US by continuing to transition to natural gas, while we keep building a lot of wind and solar, and at least maintaining our nuclear output (ideally we'd double that, but...).
- mirimir 8y agoOK, I get that. Methane, even without CO2 capture, is better than coal.
- donarb 8y ago> We should very aggressively pursue the use of natural gas until all coal plants are shuttered. The administration is now proposing that grid operators be forced to buy electricity from coal and nuclear plants that are now in the process of being shut down. The excuse is "national security". https://www.bloomberg.com/news/articles/2018-06-01/trump-said-to-grant-lifeline-to-money-losing-coal-power-plants-jhv94ghl https://www.bloomberg.com/news/articles/2018-06-01/trump-sai...
- manicdee 8y agoYes. The comparisons of CO2 output aside, methane mining is increasingly being shown to be a major contributor to methane in the atmosphere. Being a far more potent greenhouse gas than carbon dioxide, we need to minimise the production of methane, rather than increase it. https://www.theguardian.com/environment/2016/oct/26/what-is-causing-the-rapid-rise-in-methane-emissions https://www.theguardian.com/environment/2016/oct/26/what-is-... As far as renewables go we have options including wind power which are already cheaper than natural gas plant: https://cleantechnica.com/2016/12/25/cost-of-solar-power-vs-cost-of-wind-power-coal-nuclear-natural-gas/ https://cleantechnica.com/2016/12/25/cost-of-solar-power-vs-... So both from economic and ecological viewpoints, natural gas is a bad idea.
- mirimir 8y agoBut still better overall than coal, perhaps?
- manicdee 8y agoIf you are switching away from coal, the economically sensible decision is renewables. The ecologically sensible decision is also renewables. Switching to gas is just trading one version of disaster for another. Instead of your world being razed by Godzilla you spend lots of money so it gets razed by Hedorah instead.
- adrianN 8y agoBut coal and renewables are very different, unless you also buy lots of storage.
- manicdee 8y agoThe issue has been done to death in academic circles. All we need to do is stop subsidising coal and nuclear, focus on investing in (companies rolling out) renewables, and let the propeller heads get the job done. Here's one recent take on the issue: https://reneweconomy.com.au/a-100-renewable-grid-isnt-just-feasible-its-already-happening-73505/ https://reneweconomy.com.au/a-100-renewable-grid-isnt-just-f... Note that last bit: as we shift to a transport fleet consisting of more and more EVs, the possibility of using storage to balance out demand vs supply becomes more likely, without huge investment in utility scale static batteries.
- pjc50 8y agoSo long as oil is in demand, there is methane as a byproduct. Both from conventional drilling and fracking. If it's not used it will be "flared": burnt directly to the atmosphere with no useful byproduct. E.g. http://www.naturalgasintel.com/articles/114565-bakken-natural-gas-flaring-high-priority-for-north-dakota-industry http://www.naturalgasintel.com/articles/114565-bakken-natura...
- mirimir 8y agoHuh? Methane is a versatile feedstock. Haber process for ammonia. Also methanol and acetic acid, and from them, just about anything.
- pjc50 8y agoYes, but we don't need that much of it for chemical purposes and it's burnt in huge quantities because it's a pain to ship and low value. Nigeria flares something like 700 million cubic feet of gas every day due to lack of transport infrastructure.
- microcolonel 8y agoSeems like a quick and dirty (and cheap!) thermal engine would be a big upgrade, compared to just burning it. Not the sort of thing your average "environmentalist" would be into, though.
- thinkcontext 8y agoIf it were economic to do that don't you think it would be done? Oil companies have been at this for a while and are not known for throwing away money. The basic problem is wells are remote and flaring is intermittent. Why would environmentalists have a problem with flaring versus using the heat from combustion to do something? Environmentalists would be in favor of putting a price on the CO2 emitted from burning or perhaps limiting oil production that leads to flaring.
- semi-extrinsic 8y agoActually, this isn't very complicated compared to a modern high-efficiency gas (combined cycle) powerplant or coal (integrated gasification) powerplant, especially when you take into account the exhaust cleaning systems to remove NOx and CO and other nasties that those existing options need. As I understand it, the new research needed to make this happen is on making new components work (like the high pressure supercritical combustor they mention in TFA). The process complexity isn't anything remarkable. As for PV: we are nowhere close to having feasible mature solutions for large scale day-to-day (or even intra-day) energy storage. Take the "world record" Tesla system in Australia that gets talked about a lot. In the hypothetical (and IMO entirely unfeasible) scenario where Australia switches to PV to replace coal and gas, and you wanted to use this Tesla solution to store energy from one day to the next to cover just a 20% variability in PV electricity production, you'd need to install more than 10 000 such facilities, at a cost of the order of magnitude of 1 trillion USD. For Australia alone. So since we don't have that kind of energy storage, we need at the very least 40-50% baseline generation capacity from gas turbines (CO2-emitting or clean), hydroelectric and nuclear power.
- mhandley 8y agoIf you're trying to cover a 20% variability in PV from day to day, isn't it cheaper to just 20% overprovision PV? You can use the spare electricity on good days for desalination or aluminium smelting, or something that doesn't mind an intermittent cycle.
- rhino369 8y agoPV output at different stations are pretty highly correlated. I also think that variability is a lot more than just 20%. I think there is 50% variation between December and July in most of the USA just based on sunlight.
- pjc50 8y agoYes, seasonality is big and gets bigger the further north you go. I'm at 56N and recorded data to make a graph: https://flatline.org.uk/daystats.html https://flatline.org.uk/daystats.html
- gwbas1c 8y agoThe short answer is that we don't know how to economically stockpile energy created by solar panels for the winter. I just set my house up to be very close to "net zero" with electric heating and one plug-in vehicle, but the system works by overproducing in the summer and underproducing in the winter. The cost would be double or triple if the system had batteries and was capable of generating enough energy to heat my home in the winter.
- xelxebar 8y agoRegarding energy production and climate in general, the sheer abundance of data and articles has, overall, left me feeling less informed than when I started. However, another HNer introduced me to this amazing site: https://ourworldindata.org/ https://ourworldindata.org/ and so far I've found it to walk a great balance between accessible and rigorous. The articles seem to be well and reliable sourced, which provides good launching points for further investigation. Anyway, just wanted to pass it forward, per se.
- sergiomattei 8y agoGreat link! Spent quite a while checking several statistics... Bookmarked. Super interesting stuff.
- gwbas1c 8y agoRegarding these kinds of plants that operate by burning: We don't know what "stockpiled" solar energy will be. Some people think it'll be hydrogen. Other people think we'll figure out how to generate flammable gasses like methane, propane, natural gas, ect, from sunlight. Historically, steam turbine plants get retrofitted to run on different fuels. I think there's a good chance we'll figure out how to stockpile a flammable gas from solar energy, and then retrofit these kinds of plants to use it. In this particular case, capturing CO2 is interesting, because stockpiling solar energy to a flammable gas may require a source of pure CO2. Thus, this plant could stockpile CO2 in the winter when sunlight is less abundant, and then stockpile fuel in the summer when sunlight is more abundant.
- lumberjack 8y agoThere are many entities claiming they found some chemical process that outputs a flammable gas (or heat) and the whole process is carbon negative, somehow. But all of these claims are all vapourware, still.
- jjoonathan 8y agoI thought air-to-fuel was old school chemical engineering that nobody has figured out how to make economical. The "somehow," though, I believe is known.
- Retric 8y agoCarnot efficiency limitations means the winning solution can't use burning CO2. Batteries and hydro can both break 90% round trip efficiency while having very low costs. To win something needs to be better than that or very cheap, and burring stuff is not cheap.
- gwbas1c 8y agoMaybe, but keep in mind that batteries are expensive and energy intense to manufacture. When a battery goes through many cycles in a year, the cost and energy investment are marginal. The problem is stockpiling. If we have a lot of solar, we will need to stockpile energy in the summer for the winter. Buying a giant battery that charges in the summer so I can run an electric heater in the winter is probably more expensive than figuring out how to manufacture a flammable gas. If I use it for 20 years, and take into account the energy used to manufacture, I wonder what the "true" efficiency is? It's still very affordable to heat with wood, (which captures CO2 from the air,) so I'm rather confident we can figure out how to do this at scale.
- gameswithgo 8y agoThis doesn't seem to keep co2 out of the atmosphere, it just lets them sell it before its released.
- saas_co_de 8y ago"The mostly pure CO2 can then be sold to oil fields for use in enhanced oil recovery" The CO2 is pumped under ground to force oil out. "In these applications, between one-half and two-thirds of the injected CO2 returns with the produced oil and is usually re-injected into the reservoir to minimize operating costs." https://en.wikipedia.org/wiki/Enhanced_oil_recovery#Liquid_carbon_dioxide_superfluids https://en.wikipedia.org/wiki/Enhanced_oil_recovery#Liquid_c... Since this oil will be burned creating more CO2 the total atmospheric CO2 increase is probably greater than just a plain power plant with no capture.
- gameswithgo 8y agoI imagine it doesn't stay trapped in the ground forever either, at least not always.