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Large-scale ‘sand battery’ goes online in Finland

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Re: Large-scale ‘sand battery’ goes online in Finland

#71

Post by GekkePrutser »

konschubert wrote: post #15
pavon wrote: post #8

As an American it completely breaks my expectations that district heating not only works can be more efficient that decentralized heating. The amount of heat lost just moving water from the water heater on one side of the house to the shower on the other is ridiculously high in houses here. The idea that you can insulate well enough to efficiently move heat across a city is amazing to me.

As a German living in a city with mandatory district heating... the end result is to be that people seem pay more for heating than they would with a decentralised system. I think that's mostly due to the high upkeep costs of the system, though, the transmission loss is quite manageable, I think. Of course there are arguments to be made that when accounting for the cost of installing a heating system, and the space it…

Yeah I'd hate having District heating. A friend had this in the past and she couldn't even regulate it. The house was way too hot for her.

It would not work for me as I usually have the house around 16 degrees C in winter. Needless to say my energy bill is very low :)

Re: Large-scale ‘sand battery’ goes online in Finland

#72

Post by throwaway742 »

ethagknight wrote: post #51
com2kid wrote: post #40

Earlier quoted context omitted.

> As a German living in a city with mandatory district heating... the end result is to be that people seem pay more for heating than they would with a decentralised system. So, in America, it is very common for hot water tanks to suddenly fail, leaking water everywhere and causing massive amounts of property damage and even creating health hazards through mold. In a not-insane world, all hot water tanks would come wi…

This comment is wrong on many levels. Hot water heaters should last a lot longer, and when they fail it’s probably a faulty thermostat or short. Still, water heaters get a drain pan to catch leaks. Lastly, installing a leak detectors are trivial and common. Your condo may have been a bad install or not installed to code. America moves hot water just fine. EDIT: yes water heaters can fail. Usually due to bad install,…

One problem is that people never replace their sacrificial anode. Most people don't even know it exists.

Re: Large-scale ‘sand battery’ goes online in Finland

#73

Post by hahaitsfunny »

_0ffh wrote: post #70
hahaitsfunny wrote: post #69

Earlier quoted context omitted.

Quoted post unavailable.

Where I come from in Europe, things look even more suicidal. Electric power futures for mid-2023 are currently traded at ten-fold the price of electric power one year ago. The end seems uncomfortably nigh.

Yeah, well Europe becoming more dependent on US crude which is 5x more expensive than cheap Russian crude (which more of would have flowed into Europe if Nordstream 2 had been completed) is exactly what the US petroleum companies want. Biden and those who support his administration are using this as an opportunity to push their green energy agenda here in the US, and most of the equipment manufactured for solar comes out of China.

Re: Large-scale ‘sand battery’ goes online in Finland

#74

Post by karpierz »

zmgsabst wrote: post #61
thematrixturtle wrote: post #55

Earlier quoted context omitted.

It's factual. The gas supplies in question were not covered by sanctions, but Russia tried to unilaterally switch to being paid in roubles and were told to go batter sand (bada bum tssh).

> gas supplies in question were not covered by sanctions, but Russia tried to unilaterally switch to being paid in roubles I don’t think this is a very honest characterization: Russia demanded payment on their terms only after they were kicked out of SWIFT and their reserves frozen by foreign banks. I don’t think I’d describe that change in payment terms in response to bank sanctions as “unilateral” or unrelated to s…

> Russia demanded payment on their terms only after they were kicked out of SWIFT and their reserves frozen by foreign banks.

If only there was something Russia could do to stay in SWIFT and not be hit by sanctions....

Re: Large-scale ‘sand battery’ goes online in Finland

#75

Post by samatman »

mwint wrote: post #58
samatman wrote: post #46

Earlier quoted context omitted.

Volume to surface area: for every doubling of diameter you have 1/16th the losses, before factoring in insulation. 1/16th probably sounds high, but the extra halving is because flow rate increases as radius^4, not cubed as one might guess.

Naively, I would have guessed flow rate to increase as radius^2 (cross sectional area). Guessing the reason for extra increased flow is some edge effect / turbulence mechanisms?

Center flow at a given pressure is also square the radius.

Re: Large-scale ‘sand battery’ goes online in Finland

#76

Post by f7fg_u-_h »

hedora wrote: post #54
com2kid wrote: post #40

Earlier quoted context omitted.

> As a German living in a city with mandatory district heating... the end result is to be that people seem pay more for heating than they would with a decentralised system. So, in America, it is very common for hot water tanks to suddenly fail, leaking water everywhere and causing massive amounts of property damage and even creating health hazards through mold. In a not-insane world, all hot water tanks would come wi…

There’s a cheap ($20?) add on for our water heater that adds a conductivity sensor in the drip pan, and a shutoff valve on the inlet. There’s a slightly more expensive variant from another company that supposedly looks at flow for the whole house, and cuts water off due to slow leaks or burst pipes. I’m shocked that the water heater cutoff valve isn’t required by code. In contrast, plumbed drain lines for water tank…

Did you manage to realize any insurance savings? Or do the BigCo's just not care if you monitor it right?

Re: Large-scale ‘sand battery’ goes online in Finland

#77

Post by dubswithus »

bluSCALE4 wrote: post #36
ortusdux wrote: post #31

Earlier quoted context omitted.

I'm looking at going this route before I finish the basement. The master shower is the furthest point from the heater, and it takes a solid 2-3 gallons to get hot water in the morning. The math didn't make sense until I put in a heat-pump water heater. Now I average $170/year to heat my water, and the recirc should only add ~$30/year. My pipes are well insulated, but I'm in a colder climate so loosing heat into the w…

I installed a recirculating pump and had it on the timer. But then for some reason, I switched it to always on and it's so much nicer. Hot water is always hot.

I’ve been tempted to do that. Sometimes I wake up at odd hours when it’s not running.

Re: Large-scale ‘sand battery’ goes online in Finland

#78

Post by timbit42 »

FastMonkey wrote: post #2

What's the round trip efficiency of something like this, and what's the rate of loss to the environment? There's been a couple of these posted in the last few days and I have no feel for these numbers.

The sidebar on this article claims efficiency "up to 99 percent". OK, but what is typical?

https://www.dailymail.co.uk/sciencetech/article-10982885/Wor...

Re: Large-scale ‘sand battery’ goes online in Finland

#79

Post by Retric »

barbazoo wrote: post #47
LegitShady wrote: post #44

Earlier quoted context omitted.

its only ~50 homes

> Optimal community size would be 200-300 homes to realize the economies of scale. The number of systems would remain the same; only the number of boreholes would need to increase Decentralized systems like this one are cheaper and faster to build so it makes sense that the number of households served is on the low end. That doesn't mean it's not useful tech.

It’s interesting. 7 million in support to supply 97% of annual heat for 52 homes isn’t that far off being reasonable for an early R&D project. An 80% price drop at modest scale, say 100 different 300 home subdivisions actually seems achievable.

I think it’s largely a question of how dependent this is on local geology.

Re: Large-scale ‘sand battery’ goes online in Finland

#80

Post by AnssiH »

GekkePrutser wrote: post #71
konschubert wrote: post #15

Earlier quoted context omitted.

As a German living in a city with mandatory district heating... the end result is to be that people seem pay more for heating than they would with a decentralised system. I think that's mostly due to the high upkeep costs of the system, though, the transmission loss is quite manageable, I think. Of course there are arguments to be made that when accounting for the cost of installing a heating system, and the space it…

Yeah I'd hate having District heating. A friend had this in the past and she couldn't even regulate it. The house was way too hot for her. It would not work for me as I usually have the house around 16 degrees C in winter. Needless to say my energy bill is very low :)

That's not a thing here, everyone has controllable thermostats (Finland).
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