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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

#141

Post by KennyBlanken »

com2kid wrote: post #53
ethagknight wrote: post #51

Earlier quoted context omitted.

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,…

> Lastly, installing a leak detectors are trivial and common. I've told about a dozen people in my life that leak detectors were a thing, and they were all shocked at the info. From what I gather, their existence is not common knowledge. > Still, water heaters get a drain pan to catch leaks. Initial leaks yes, but eventually hot water heats fail in a dramatic fashion and spew water everywhere. > Your condo may have b…

Tanks don't fail unless the anode gets depleted.

You seriously need to tell your condo association to get their maintenance people to flush the water heaters regularly (seasonally or annually) and check/change the anodes. If they're gas-fired heaters, the burner and air intakes should be getting cleaned.

If this isn't being done, it's probably because your maintenance is being done by plumbers, who have convinced everyone that "they just fail, you know?"

Replacing a tankless water heater because the motor has failed is silly. You replace the motor. And tankless heaters don't fail very often unless, again, they don't see regular maintenance. As in: flush/descale annually and water/air filter cleanings.

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

#142

Post by UkrainianJew »

WalterBright wrote: post #113
tjmc wrote: post #101

Earlier quoted context omitted.

HVAC engineer here. At the residential level this is already achievable with hot water storage from either solar thermal and/or heat pumps. Plus you get to use the hot water (assuming you've sized the tank correctly!) Storing heat in rocks or sand doesn't make sense from a thermal efficiency standpoint unless the temperature is high and that isn't economically viable unless you have large volume storage - typically d…

How can it not be efficient? The heat to heat a rock is 100% recovered when the rock cools back down. A tank of water works, too, but tanks rust, mildew, and leak.

Heat keeps leaking out. The amount of stored heat is proportional to the cube of the linear size, the leak rate is proportional to the surface area (square of the linear size). Hence, the bigger the storage, the higher the efficiency.

Same why a flea can jump >10x its height, and a human cannot (square growth of strength, cubic growth of weight).

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

#143

Post by japanuspus »

Symbiote wrote: post #28
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…

I find district heating in Copenhagen to be good value, and it seems to be a good deal greeted. https://celsiuscity.eu/district-heating-prices-highly-compet...

One reason Denmark has very affordable district heating is that it is based on "waste heat" from power plants, and "waste heat" is exempt of energy taxes (because those are paid on the primary energy sale, i.e. the electricity).

This comes with some perverse incentives in an age of renewables:

1. If the power plants use surplus electricity to provide district heating it is no longer a "waste product" and consequently taxed. Since the power plant cannot run without generating electricity, this leads to periods of negative power prices.

2. Cooling water from e.g. data centers is too cold for district heating, but it would be energy efficient to use heat pumps to extract that energy. This is not done, because the product would be subject to full energy taxes as it is not a waste product.

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

#144

Post by albertopv »

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…

I remember in a different way.

Gas related banks were not included in first SWIFT sanctions, other banks were.

They were only after Russia pretended to be paid in rubles. Of course that demand was driven by sanctions.

If fact that gas related banks were left out of first sanctions was quite controversial, many saw that as a weak european move as europe is still unable to live without russian gas.

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

#145

Post by com2kid »

pickup191 wrote: post #133
com2kid wrote: post #62

Earlier quoted context omitted.

> 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. Oh I know, they are awesome. They should come standard, and more people should know about them. It is one of those things I try to bring up in conversations at random, because holy crap the # of people I know who have had water damage from their water heating dramatically failing is…

What’s the name of this 20 dollar device?!

Just a water tank moisture detector, e.g. https://a.co/0ujkOuD

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

#146

Post by kitd »

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.

I once visited a geothermal plant about 20km outside Reykjavik that supplies hot water for heating the city. Even in the depths of Icelandic winter, the temperature only drops 1 deg C between the plant and the city. A lot of Rockwool around the pipe IIRC.

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

#147

Post by lachstar-x »

karpierz wrote: post #74
zmgsabst wrote: post #61

Earlier quoted context omitted.

> 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....

Why stay in SWIFT when it's been demonstrated that they can be cut off from global supply on the whims of the US administration? That one decision did more for the death of the American empire than any other.

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

#148

Post by moistly »

WalterBright wrote: post #95
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…

> 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. I've had them fail and leak many times. But I had the water heater put in the basement next to a floor drain, and the floor slopes slightly towards the drain. No damage whatsoever from leaks, and it wasn't an emergency to get it fi…

The BC Building Code mandates a floor pan under the HWH, draining into the wastewater system. The floor will be sloped as well, and the drain within X distance of the heater. I expect it’s a Canadian national standard.

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

#149

Post by benj111 »

throwaway742 wrote: post #125
1123581321 wrote: post #96

Earlier quoted context omitted.

They last as long as the expected tank life these days. Tanks with longer life rating use powered rods.

>They last as long as the expected tank life these days. Kinda seems like a self-fulfilling prophecy or one could even say planned obsolescence.

Or an accurate estimate???

I don't really get how you can extract a conspiracy out of something lasting as long as the manufacturer expected it to last.

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

#150

Post by quickthrower2 »

dubswithus wrote: post #52
Nick87633 wrote: post #37

Earlier quoted context omitted.

I wash my hands with the cool water that initially comes out?

Cool water? What about freezing water in the winter?

I am still waiting for the freezing water to come out of the tap.
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