If you put it in the ground, yes. There are papers on production temperature of biochar, and it seems as though lower temperature charcoal is better for heating use, as it retains some of the oils that get driven off in higher temperature production (yields in pounds out vs pounds in are lower in higher temperature work, yet the product is higher percentage carbon), yet, it is not clear this matters substantially for biochar.
Climate change tech (not just renewables)
- Thread starter bjn
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If you put it in the ground, yes. There are papers on production temperature of biochar, and it seems as though lower temperature charcoal is better for heating use, as it retains some of the oils that get driven off in higher temperature production (yields in pounds out vs pounds in are lower in higher temperature work, yet the product is higher percentage carbon), yet, it is not clear this matters substantially for biochar.
Another approach to low carbon concrete. This time in the form of recycling. Take concrete you’ve recovered from a demolition and use it for flux in place of limestone when making steel. The concrete gets turned back into Portland cement. No extra CO2 emissions and you are getting a two for one form the energy used to make the steel. They can use this with arc furnaces recycling steel. The podcast says that up to 1/3 of the world’s concrete can be made this way. Which I find somewhat surprising.
https://www.theguardian.com/science...ur-biggest-building-material-go-green-podcast
https://www.theguardian.com/science...ur-biggest-building-material-go-green-podcast
That is simply fabulous news.
For those like me who would rather read than pod:
https://www.nature.com/articles/s41586-024-07338-8https://www.sciencedaily.com/releases/2024/05/240522130434.htm
Electrochemistry seems to be one of the things that may help save us from ourselves. One application being researched is to decarbonise ammonia production, replacing the Haber-Bosch process that intrinsically emits CO2 as it uses methane as a hydrogen source.
There are a range of papers out there on this (Duckduckgo is your friend). A nice summary paper is on science direct that covers various approaches. They all center around room temperature reactions using lithium plated electrodes. A paper published last month details an experimental continuous flow reactor that ran for 60 hours with a Faradic efficiency of about 64%. The podcast where I first heard about this was interviewing an author of this paper.
If this works out the capital cost should be much less than a massive HB plant and be able to be built nearer the point of use. The main cost would be in electricity, but you aren’t paying a penny for fossil gas
There are a range of papers out there on this (Duckduckgo is your friend). A nice summary paper is on science direct that covers various approaches. They all center around room temperature reactions using lithium plated electrodes. A paper published last month details an experimental continuous flow reactor that ran for 60 hours with a Faradic efficiency of about 64%. The podcast where I first heard about this was interviewing an author of this paper.
If this works out the capital cost should be much less than a massive HB plant and be able to be built nearer the point of use. The main cost would be in electricity, but you aren’t paying a penny for fossil gas
The other potential use for electrochemistry is direct reduction of iron ore to iron metal. Why yes, I did happen to listen to the Volts podcast this week, but I did know about the idea just not how far it has come. Boston Metal seems to be leading the game at the moment and has significant investors. The hard part seems to be making electrodes that can handle the extreme temperatures. They also refine other ores, not just iron, and expect their first commercial plant to start operating this year in Brazil, refining precious metals, and their first iron plant in 2026. They can also work with lower quality ores than traditional blast furnaces can, including existing spoil heaps. Hopefully this works out as well.
This begs a question. The two main uses envisioned for green H2 is to replace fossil gas in ammonia production and to replace coke when reducing iron ore to iron. Will green H2 hype be a bust? All the other use cases envisioned seem to be relatively minor in comparison, with the just maybe exception of seasonal energy storage.
This begs a question. The two main uses envisioned for green H2 is to replace fossil gas in ammonia production and to replace coke when reducing iron ore to iron. Will green H2 hype be a bust? All the other use cases envisioned seem to be relatively minor in comparison, with the just maybe exception of seasonal energy storage.
Fair enough, but it won’t be used for ground transportation.
AIUI, marine shipping CO2 emissions are about 1/4 that of steel production and a bit more than ammonia based emissions.
FWIW, about 40% of high seas shipping is moving fossil fuels about the place. Decarbonising steel production would also reduce the amount of met coal shipped and so further reduce emissions. About 40% of the coal exported from Australia is met coal, so it’s not a small proportion of shipped goods.
AIUI, marine shipping CO2 emissions are about 1/4 that of steel production and a bit more than ammonia based emissions.
FWIW, about 40% of high seas shipping is moving fossil fuels about the place. Decarbonising steel production would also reduce the amount of met coal shipped and so further reduce emissions. About 40% of the coal exported from Australia is met coal, so it’s not a small proportion of shipped goods.
Harking back to the first post in this thread, Sublime Systems have just inked their first major deal which is to supply Microsoft with 625,000 tons of low carbon cement made with their electro chemical process and not from burning limestone. The guaranteed cash flow should help them expand. Nice to see that they are moving out of prototype into production. Hopefully this proves economically viable and they grow quickly.
The deal is party to deliver actual cement for constriction near their plant, and partly in the form of “environmental attribute certificates” for construction too far away. The certs appear to be payments that subsidises the cost of cement production for sale to others.
https://www.linkedin.com/posts/subl...ent-offtake-activity-7331304179438686208-a9R2
Edit to add details about the certificates.
The deal is party to deliver actual cement for constriction near their plant, and partly in the form of “environmental attribute certificates” for construction too far away. The certs appear to be payments that subsidises the cost of cement production for sale to others.
https://www.linkedin.com/posts/subl...ent-offtake-activity-7331304179438686208-a9R2
Edit to add details about the certificates.
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It's interesting technology. They claim to be at or near cost parity with making cement in a kiln and with a 90% CO2 emission reduction.
There's an extremely low-tech experiment in Sydney that's proven to be very effective - coaxing fast-growing vines to shade parking lots!
They have proven to drop the surface temp in these car parks by as much as 35C (from 70C to 35C) on the asphalt, which is a huge difference and helps to cut down on the hot-spots, in particular in areas that often hit 45C during mid-summer heatwaves.
They've been in place for 3 years and have about another 2 years to go before the trellis' are fully covered. Wisely, they've made the mesh that the vines grow on such that birds can't rest on it (so no bird-poop on the cars) and the vines they've used don't drop fruit.
Looks like a simple, effective win-win with extremely low-tech and low investment cost!
They have proven to drop the surface temp in these car parks by as much as 35C (from 70C to 35C) on the asphalt, which is a huge difference and helps to cut down on the hot-spots, in particular in areas that often hit 45C during mid-summer heatwaves.
They've been in place for 3 years and have about another 2 years to go before the trellis' are fully covered. Wisely, they've made the mesh that the vines grow on such that birds can't rest on it (so no bird-poop on the cars) and the vines they've used don't drop fruit.
Looks like a simple, effective win-win with extremely low-tech and low investment cost!
Maybe this is a silly question, but if you’re already installing supports and the mesh structure, why not install a regular parking shade? It wouldn’t take five years to grow, and as a bonus, it would also block rain.
It's also a fantastic place to install urban PV.
Against PV: panels are cheap but not free, inverters still cost money, and someone has to pay for a connection / meter.
Also support has to be waaaaay sturdier than that mesh and a few sticks they use now. But yeah, PV would be great, it's only a matter of time until there is plenty batteries to charge so PV is never wasted.
Oh and a plant also emits water vapor to cool down the surroundings, that is absent with PV or a cloth.
Also support has to be waaaaay sturdier than that mesh and a few sticks they use now. But yeah, PV would be great, it's only a matter of time until there is plenty batteries to charge so PV is never wasted.
Oh and a plant also emits water vapor to cool down the surroundings, that is absent with PV or a cloth.
I'm also interested to know if there are benefits to doing it this way.
Possible advantages I can think of (no idea if real or significant enough to matter):
- self-healing: less chance of permanent damage from storms, less maintenance required
- self-renewing: not really a target for graffiti and would erase it on its own if it was targeted, less maintenance required
- Cheaper? Maybe? Less material needed, at least, particularly metal if they want something sturdy that lasts
- Aesthetics?
- Serves as a carbon sink?
Also from the article it sounds like they expect fewer birds to nest in it, but I have my doubts in that area. Especially once the vines are established, the mesh being designed to discourage birds won't make much difference.
Plants transpire, which evaporates water and so both help to humidify the area and lower local air temperatures, along with the benefit of nice green leafyness, suppression of dust and the shade thing.
I would rather give growing space to some native vines, preferably something which supports native pollinators or otherwise provides habitat. I don't need more steel/concrete/plastic/asphalt shit. We have plenty. If you want hardscape, at least make it a solar canopy.
Not sure what you mean by a "regular" parking shade. Even a tarp is going to need more beefy support to withstand wind gusts compared to vines. Doubly so if you're talking corrugated steel. Gusts would at least somewhat flow through the vines, possibly ripping off leaves and further reducing sail area. Then (as noted) the vines would largely self-repair.
Yeah, the overall intention is to look at ways to implement low-impact, low-maintenance solutions and vines are hard to kill and as mentioned can regrow after storm damage etc. There are a lot of other places where PV is being put on the parking lot covers (in particular in large shopping centres/supermarkets etc) and this is just another option being trialed.
There's a push generally towards re-imagining (large) parking lots towards being much less of a burden on the local environment. They act as a large low-albedo surface, adding to the urban heat island effect. They're large paved areas which exacerbate storm runoff-driven flooding events. And they're terrible places to be as a human.
So a better approach is to have as little pavement as possible. Triodos recently opened their new headquarters with something approaching the state of the art:
https://www.triodos.nl/binaries/con...k-nederland.jpg/triodoshippo:heroImageDesktop
It's got permeable pavement (permeable ZOAB for the driving surfaces and I think gravel composite for the parking spots themselves), all spots that don't need to be paved are grass and the solar canopy empties into the local landscape, not storm sewers, slowing storm surge. There's still some ways in which this isn't a great parking lot, e.g. there aren't good protected walking corridors and the perpendicular parking situation requires more hard pavement than a herringbone setup.
So a better approach is to have as little pavement as possible. Triodos recently opened their new headquarters with something approaching the state of the art:
https://www.triodos.nl/binaries/con...k-nederland.jpg/triodoshippo:heroImageDesktop
It's got permeable pavement (permeable ZOAB for the driving surfaces and I think gravel composite for the parking spots themselves), all spots that don't need to be paved are grass and the solar canopy empties into the local landscape, not storm sewers, slowing storm surge. There's still some ways in which this isn't a great parking lot, e.g. there aren't good protected walking corridors and the perpendicular parking situation requires more hard pavement than a herringbone setup.
Recent Volts podcast with the co-founder of Dandelion Energy is well worth digging into - as some may recall, their focus is lower cost, ground source heat pumps (GSHP) for residential. Spun out of Google X in 2017.
Dandelion built up enough success with "one-off" type retrofits in the NE US that they landed a deal with Lennar to install GSHP systems for 1,500 new-build homes in the Denver area.
As with many things, scaling and repeatability is super important for GSHP in the USA because the current market is so tiny. Apparently getting this deal will allow them (and their suppliers) to cut costs significantly, which should be carried over to other projects.
So much like we have seen with electricity-production geothermal, there's huge opportunity for learning curve improvements - but the needed scaling still has a long way to go if we want a nation-level impact on climate change.
Dandelion built up enough success with "one-off" type retrofits in the NE US that they landed a deal with Lennar to install GSHP systems for 1,500 new-build homes in the Denver area.
As with many things, scaling and repeatability is super important for GSHP in the USA because the current market is so tiny. Apparently getting this deal will allow them (and their suppliers) to cut costs significantly, which should be carried over to other projects.
So much like we have seen with electricity-production geothermal, there's huge opportunity for learning curve improvements - but the needed scaling still has a long way to go if we want a nation-level impact on climate change.
What's their secret vs established players like (global) Daikin, LG and (European) Nibe? (+ too many others to mention, I kept it to 1 per region)
You cannot get a new gas connection in the Netherlands anymore so these are selling in decent volume. Most projects drill a vertical well, 1 per home, some near water do heat exchange into open water that never freezes like major rivers.
You cannot get a new gas connection in the Netherlands anymore so these are selling in decent volume. Most projects drill a vertical well, 1 per home, some near water do heat exchange into open water that never freezes like major rivers.
It's an american thing. GSHPs in the US are immensely expensive, like, 3-10x the cost here, for all the same reasons that solar and basically anything else is so expensive there. A lot of the things that make this stuff work in Europe don't exist in the US. The market is too small for any real competition and the market is also too small for specialized companies doing just one thing really well (e.g. mud drilling wells with specialized rigs).
Dandelion is essentially doing what everybody else in the HP world has already done: give people a bundle deal and negotiate with suppliers/subcontractors for better prices on bigger volume. Obviously, that only works if you have that volume.
Aah so basically scaling installs. I thought they had some killer tech no one else had as their marking is mostly tech focused.
One additional item from the podcast is adapting the tech to the US market. A US home typically uses forced air heating instead of hot water or steam - and apparently where radiators are used they tend to be hotter and smaller.
edit: moved to the "Can renewables replace fossil and nuclear fuels?" thread
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Installers look at me like I have two heads when I ask for a ducted unit. I don't want one stupid thing on the wall per room, I just want it to be cool, is that so weird? Next / the dream house will get rid of all in room units and replace them by at least ones hidden in the hallway a la hotel rooms.
Going outside of what sells in bulk adds a ton of friction, good of Dandelion to try something else and scale it up so it becomes the norm. Taking a better loop, I think their unique selling point is the drilling service. Here, no way LG / Daikin etc sends out a crew and a rig but we drill often enough that you have multiple vendors doing it.
Interesting how they just go water - air exchange and that's it; most units here go water - water and then water - air using a fancoil, making deployment super flexible and providers hot water for showers via a big boiler / buffer vat. But that requires the (whatever source) heat pump to produce seriously hot water, 120F/50C minimum, and once a week 60C to kill anything that lives in the tank.
First time I've seen a technical tour of Redwood Materials - JB Straubel himself was showing Sandy Munro around. Some key takeaways:
- Currently have 70-75% of the US lithium battery recycling market
- Just about any lithium chemistry
- 20-25 GWh/year run rate today
- Current equipment scaled up to ingest up to ~20 kWh chunks of battery pack
- Continuing to scale and automate
- Significant fraction of incoming material is factory waste such as trimmings or cells which fail QC
- Packs in good shape may be included in their stationary storage, paired with solar (I think he said 20 MW currently) and feeding power to a datacenter 24/7 at a price below utility rates.
- Recycling operation is profitable, without government incentives.
I'm guessing that having hot water and general house heating coming off the same boiler is pretty common over there. US houses usually have a standalone water heater.
It's just that heat pumps are rather expensive so having both off the same heat source makes sense. Otherwise you still need gas or worse, an electric boiler for hot water?
I guess you can patch it with an air source heat pump boiler using inside air but those are not silent.
In Spain we are seeing a lot of small heat pumps with integrated water tank just for heating water. They are cheap (starting <€1000) and combined with inverter mini splits for space heating/cooling are good enough for apartments and small houses.
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I'm planning on replacing* my gas water heater with an ASHP version - what I would really like to do is have ducting set up so that I can choose whether the cool exhaust air goes into the house or outside, depending on the season.
*Still waiting to see whether the HEEHRA/Homes/HEAR/Inflation Reduction Act incentives actually happen in Texas, or if they get gutted.
There's a bunch of brands that have this, they have (usually automatic) valves to switch exhaust air between going inside or out.
However... this isn't as good as it seems:
- If you have an airtight house, you don't want to have unbalanced air inlets/exhausts, that's going to cause extra heat load elsewhere, and...
- That heat load is probably larger than the advantage you can take from your heat pump water heater, because...
- It usually heat exchanges between inlet and exhaust somewhat beyond the dew point, which means the exhaust air isn't that cold to begin with (to eliminate condensation)
In a modern house that's well-constructed, you don't get any advantage from this unless you massively overengineer this and put an enthalpy exchanger on the outlet
I’ve heard it’s more useful in terms of a dehumidifier. But if it’s non-condensing I guess not.
Thanks for the info - the backup plan is to have it dump cool air into the garage in the summer. Current water heater is in the garage, the wall behind it is part of the house envelope proper.In a modern house that's well-constructed, you don't get any advantage from this unless you massively overengineer this and put an enthalpy exchanger on the outlet
Condensing variants exist, even room air types exist that don't have a vent going outside. Both would be better for local cooling and/or dehumidification, although then you end up with the problem that they typically don't have a convenient tube to connect to.
Air-source heat pump boilers now typically have the vent going outside (often concentric to make installation easier - just one hole in your house) because they're aimed at cooler climates (northern Europe, canada, etc.) where anytime you get useful dehumidification from them, it's cold outside and the air is already dry. Anytime it cools a lot (i.e. you need more hot water), it's cold already. So they don't optimize for that use case. But like with Dandelion, there are companies that optimize for more American needs.
The LG I'm looking at, https://www.lg.com/nl/ondersteuning/product-ondersteuning/cs-WH27S.F5/, has both
Optional set to connect to ducts
Condensate lines for the evaporator, so it gets rather chilly
With a simple valve you can switch between indoor and outdoor air, but make sure to flip both so you don't cause an air leak elsewhere by under/overpressure.
Nr 1 issue is the epic weight to get it up two stairs plus getting an installer to claim the subsidy.
Optional set to connect to ducts
Condensate lines for the evaporator, so it gets rather chilly
With a simple valve you can switch between indoor and outdoor air, but make sure to flip both so you don't cause an air leak elsewhere by under/overpressure.
Nr 1 issue is the epic weight to get it up two stairs plus getting an installer to claim the subsidy.
After rabbit-holing for an hour on various HPWH stuff, I think my best bet is to have a fixed air intake from the attic (directly above the current WH location) then exhaust into the garage ~9 months of the year. For the ~3 cold months, duct it outside through the existing wall vents for the current gas WH.
One bit of climate change tech I’ve found out about over the last few days is clutches.
Many grids rely on big lumps of spinning metal to provide inertia in the form of generators attached to some form of heat engine. Those heat engines are kept running in periods of high variable generation to provide grid stability services, so burning gas or whatever to keep the lump spinning.
Grids are starting to install synchronised condensers to provide grid inertia as thermal generators are starting to be shut down. For example the UK and Australia. All the spinning generator bits after the drive shaft in a thermal plant is basically a syncon. So while we have thermal generators on the grid, rather than install new syncons to provide grid stability so you can turn the burny plants off during sunny/windy periods, just put a clutch between the drive shaft and the generator so you can still provide grid stability without burning fuel. Hey presto, syncon and peaker all in one.
You can buy gas turbines with clutches, retro fit clutches to existing kit and GE even has a ‘clutchless’ gas turbine they claim can do the same thing.
Links to some marketing blah…
https://gasturbineworld.com/synchronous-condensing-demand-boosts-gas-turbine-sales/
https://www.gevernova.com/gas-power/services/gas-turbines/upgrades/lm2500-synchronous-condensing
Many grids rely on big lumps of spinning metal to provide inertia in the form of generators attached to some form of heat engine. Those heat engines are kept running in periods of high variable generation to provide grid stability services, so burning gas or whatever to keep the lump spinning.
Grids are starting to install synchronised condensers to provide grid inertia as thermal generators are starting to be shut down. For example the UK and Australia. All the spinning generator bits after the drive shaft in a thermal plant is basically a syncon. So while we have thermal generators on the grid, rather than install new syncons to provide grid stability so you can turn the burny plants off during sunny/windy periods, just put a clutch between the drive shaft and the generator so you can still provide grid stability without burning fuel. Hey presto, syncon and peaker all in one.
You can buy gas turbines with clutches, retro fit clutches to existing kit and GE even has a ‘clutchless’ gas turbine they claim can do the same thing.
Links to some marketing blah…
https://gasturbineworld.com/synchronous-condensing-demand-boosts-gas-turbine-sales/
https://www.gevernova.com/gas-power/services/gas-turbines/upgrades/lm2500-synchronous-condensing
To me it makes a lot more sense to use smart inverters on your renewables and batteries in order to provide reactive power control to the grid.
But the industry is very conservative and are far more familiar with spinning lumps of metal.
I thought the backlog on grid scale gas turbines was on the order of 5 years...
Depends on where you are. Renewables getting that last 5% is going to be hard in Northern Europe, dunkelflautes and all that, so I believe that gas turbines will be hanging around for quite a while yet, even if better solutions come up. Grid folks are justifiably quite conservative. Yes there is a backlog on new turbines, but people are also retro-fitting clutches to existing systems (can’t find the link sorry, but the example I read about was in Australia) at half the cost of a new syncon.