[HN Gopher] Why have I never heard of the Ene-Farm? (2017) ___________________________________________________________________ Why have I never heard of the Ene-Farm? (2017) Author : xhrpost Score : 49 points Date : 2022-09-02 19:09 UTC (3 hours ago) (HTM) web link (earthbound.report) (TXT) w3m dump (earthbound.report) | Animats wrote: | Panasonic still has some product info.[1] | | Natural gas powered fuel cells are available from some gas | companies.[2] | | Problems seem to be: | | * Runs at very high temperatures, around 1000C, which means | materials problems. Also, high grade heat is nice, but not that | useful for home applications. So actual sales of this technology | are to businesses. | | * There's been recent work on catalysts to bring the needed | temperature down to 500C or so.[3] That's easily managed; auto | engines run that hot. The catalyst needs ruthenium, which is | expensive, although cheaper than platinum. | | * Sulfur in natural gas messes up the process, although this can | be overcome. General problem with fuel cells: they need clean | input gases. | | * Apparently you get a lot of heat and a little electricity. This | limits the usefulness. The gas company in the US which sells this | services Maine and Vermont. | | A nice application for this would be a little unit to provide | backup power for natural gas furnaces, so you could run the fans | without external power. | | [1] | https://www.panasonic.com/uk/corporate/sustainability/produc... | | [2] | https://www.eversource.com/content/ct-c/business/services/co... | | [3] | https://www.sciencedaily.com/releases/2018/10/181029130939.h... | api wrote: | I've always been surprised that nobody has done home cogeneration | for heat and hot water. Seems like an absolute no-brainer way to | get a lot more mileage out of gas. | KiranRao0 wrote: | In Iceland, they cogenerate hot water and power due to the | abundance of geothermal. Not exactly a common case that's | replicable everywhere, but mildly interesting. | Jtsummers wrote: | You can get boilers that generate steam for radiators and hot | water for tap water. | yetanotherloser wrote: | Genuine, this-never-occurred-to-me question: are there lots | of people out there with boilers that DON'T do this, or areas | where it is not normal? | | If so - this might explain something that's been mildly | irritating me. When looking for alternatives to fuel-burning | boilers it seems easy to find positive stories about space | heating - and much less info on water heating, to the point | where it's starting to look like maybe some of these options | might not be great. Water heating is my largest home energy | usage and space heating very little because it is grossly | overrated; if you are not really unwell an indoor temperature | around 10 c is quite pleasant, so I tore my (rubbish) | radiators out in 2017 and never looked back. This is making | it surprisingly hard to figure out what replaces the boiler. | If the marketing is aimed at pure heating boiler replacers, | this difficulty is at least easier understood if not easier | solved. | projektfu wrote: | Heat-pump water heater: | https://www.ecohome.net/guides/2197/heat-pump-water- | heater-w... | | I would personally not like to live in 10degC but I prefer | hot climates. 15degC I could do. How do you keep the | temperature above 10degC? Or is the outside temp rarely | below 10degC? | yetanotherloser wrote: | Thanks! that looks technically similar to the heat pumps | aimed at space heating but a bit better - perhaps there's | an efficiency in it being meant to do just one job? It | looks like it (or its ilk) might be a good fit for me. | | Outside wobbles around -2 to 8 in winter here, inside | rarely less than 6, which is nippy but not dangerous. A | not very insulated house with solid walls (this one's | from about 1890 and has only had the easy things done) | doesn't really sink to outside temperature if you live in | it, cook, have appliances etc. There are plenty of heat | inputs, just they do another job first. Hence my interest | in water heat, I think it would start to be grim without | it. Stove for a small number of really cold evenings, | plus visitors. It would be a really bad idea to use it | all the time but it would be hard to fit a radiator-type | system to the job of "one hot room occasionally". | wffurr wrote: | I read about a Mitsubishi home gas cogeneration system many | years ago (10 ish). I think they haven't taken off because they | are expensive, only suitable in certain climates, and | significantly less efficient at producing electricity from gas | than a recent model combined cycle gas power plant. | bdcravens wrote: | So it's basically a Generac? I know that those are mostly for | backup, but my understanding that they are perfectly viable for | longer term use. (though they would need occasional maintenance) | NovemberWhiskey wrote: | If you mean "is this a reciprocating piston engine with a | generator that's plumbed for natural gas?" then no ... this is | fuel-cell technology, not internal combustion. | arcticbull wrote: | > The most important is that the electricity is generated on | site, so there are no losses in transmission. | | People really overestimate transmission losses. They averaged | only 5% in the US between 2016 and 2020. [1] | | I believe if you wanted to run a power line from Boston to LA | you'd only lose about 25%. | | [1] https://www.eia.gov/tools/faqs/faq.php?id=105&t=3 | pavon wrote: | In addition, generating electricity in a large power plant is | significantly more efficient than doing so on a small scale | even after taking transmission loss into account. | | It looks like the primary advantage of a device like this is | that you can make use of heat that would otherwise be waste. | [deleted] | digdugdirk wrote: | Interesting. It claims "95% combined heat and electrical | efficiency". I'm assuming this number is comparing immediately | after the electrical generation occurs (i.e. - this doesn't have | any transmission losses, while the electrical grid does). | | Does anyone have any comments on the comparison in overall gas -> | electrical output efficiency between large grid-scale natural gas | plants and small natural gas generators like this one? | smartmic wrote: | Wikipedia has some reasonable figures about Cogeneration fuel | cells (Ene-Farm is one of those "MicroCHP" fuel cell systems | for home usage[1]: | | > Co-generation systems can reach 85% efficiency (40-60% | electric and the remainder as thermal).[5] Phosphoric-acid fuel | cells (PAFC) comprise the largest segment of existing CHP | products worldwide and can provide combined efficiencies close | to 90% | | For the "95% [...] efficiency", I guess they take the hydrogen | heat input for calculation of efficiency. What I miss are the | losses from conversion of natural gas to hydrogen. This has to | be considered when comparing efficienies eg. with gas fired | power plants. | | So when it comes to large-scale Combined Heat and Power plants | [2], it depends. There are not only different types of power | plants (coal fired, gas fired, etc.) but also the heating part | varies (process steam, district heating, etc.). If you go | thermodynamically strict, you would also have to consider the | quality of heat (at which pressure & temperature level is the | heat extracted). This is normally not considered in the | standard efficiency formula. | | [1] | https://en.wikipedia.org/wiki/Fuel_cell#Efficiency_of_leadin... | [2] https://en.wikipedia.org/wiki/Cogeneration | i_am_proteus wrote: | I suppose there's some ambiguity in the wording... there's no | way it's 95% electrical generation efficiency. | | The key is that waste heat from electrical generation is used | to heat an otherwise-cold home, and perhaps the hot water. | | That efficiency isn't going to be possible when it's warm | outside. | jsmith45 wrote: | Gas power plants on the grid are pretty inefficient. Like a | modern furnace they are pretty efficent at getting the heat | energy out of the gas. However the efficiency of turning the | heat into electricity is low. They get something like an | average of 40% overall efficiency. The best gas turbine plants | on the market can get about 60% efficiency max. | | If the power plants were able to provide the excess heat to | nearby businesses and the like, they could be a lot more | efficient overall, and there are some that have tried to do | that, but transporting heat itself is not an easy thing to do | efficiently, and many plants are things like peaker plants, | which don't run consistently, making it even harder to sensibly | use the "waste" heat in the nearby communities. | | Then there is the grid losses. Grid transmission loses 5 to 6% | of the power in the US, making the grid 94-95% efficent. | cogman10 wrote: | Combining heat + electrical energy makes the stats really | muddy. | | Does 10% of the burned energy end up as electricity? Or is it | more like 30%? Hard to tell. | | The real question is, what do you do with that heat when you | don't want it? What's the efficiency then? | | I will say, it would be pretty neat if one day we could get a | mutli-device heat pump system going. Wouldn't it be cool if the | heat pulled from your home was dumped into the water heater | before being extracted vented? Or if instead of your fridge | having a heat pump, it simply tied into a home heat pump | system? | | This sort of thing would call for a centralized compressed | lines. And, perhaps the reason that's not happened is because | we don't want to worry about what happens when toxic gasses | discharge into the home. | | Still, would be pretty neat if we could have a centralized cold | and hot compressed gas system for buildings. | aftbit wrote: | Commercial and larger residential buildings often have water | at various temperatures as a utility. There will be a machine | room that has large water-to-water heat pumps, then a chiller | tower on the roof that takes hot water, evaporates some and | cools the rest, then returns it to the hot-side heat | exchanger. The cold side will circulate water around the | building, where it will be used in water-to-air heat | exchangers on the room or unit level to cool the building. In | most climates, larger buildings need more cooling than heat, | but doing the same thing with a hot water system is quite | common as well. | mikewarot wrote: | You could use this to power AND heat the cold side of a heat | pump, possibly getting far more than the original heat output of | the gas into a building in a cold climate that would normally be | too cold for a heat pump. | stevehawk wrote: | I'm not smart enough to know what's going on here. This is using | solar power to help make hydrogen which is then using the | hydrogen to create electricity? And then because of the heat | generated it can also be used to heat a structure (to some | degree)? | aaron695 wrote: ___________________________________________________________________ (page generated 2022-09-02 23:00 UTC)