Should new builds come with 3 phase?

[Sean.]

Just a thought, obviously solar, battery storage and heat pumps have been talked about but should we have 3 phase? My reasoning Ali's that if EVs were made to charge at 22kW that would reduce home charging times significantly, easing the use of public network rapids. It would also mean that if the grid needed to be balanced the EVs (and battery storage) could pull more to help. Would also mean that we could supply more power to the grid when needed once we have V2G. Surely the added cost of installing this at the point of construction would be minimal?

Certainly not a cheap thing to upgrade existing supplies. Much also depends on your particular DNO.

I’ve upgraded two properties in the last 10 years. Each time not much change left from £10K just in DNO charges alone. They also charge you a pro rata proportion of Tx upgrade cost if it’s established that the local supply needs reinforcement. This is the real ouch factor. I’ve heard of some doozies in terms of what the DNO wants. If you’re in the sticks, be prepared to sit down when you see the charges as it could be as much as an M3 or more.

Otherwise it give a lot of flexibility- just don’t go looking for a smart meter suppler for 3-phase as there’s only one I know of in the country that offers them at the moment and it’s not a huge market. So your stuck with AMR and HH metering.

 

[Glan gluaisne]

If these phase changed thermal store were more reasonably prices, they could be designed to sit in the corner of a kitchen under the work surfaces were in it hard to access storage space.

The first one we had was designed to fit in a kitchen cabinet, but it only stored about 4 kWh, not really enough (enough for one shower plus a bit of hand washing). IIRC, I think our 9.5 - 10 kWh unit cost around £2k, so around double the cost of an equivalent capacity hot water cylinder. Its losses are only around 25% of those of a hot water cylinder, though, so it saves around 200 to 250 kWh/year in losses. It also fits in a very much smaller space, so, overall it's not bad value. The main disadvantage is the weight. Ours weighs something like 130kg, so it's not an easy thing to move around when installing it.

 

[NorfolkMustard]

The argument made in one of the recent fullycharged videos was that 3 phase was beneficial because it makes each house able to contribute more - at higher power - to a balanced grid. they were putting in separate dedicated broadband lines to each house just for grid response comms too

 

[Sean.]

Single phase is just a penny pinching measure because Britain was dead broke after the war. All metals and especially copper were in short supply. So it was a means to an end. The European system of default three-phase connections is superior in every single way, pardon the pun.

 

[Glan gluaisne]

Single phase is just a penny pinching measure because Britain was dead broke after the war. All metals and especially copper were in short supply. So it was a means to an end. The European system of default three-phase connections is superior in every single way, pardon the pun.

I agree, just like the UK use of the damned awful ring final system for power outlets. Europe, and most other places in the world, use a far more sensible radial system, with adequate cable protection provided in the distribution board. I've lost count of the number of open rings I've found doing EICRs over the years, and not only is it a very common fault (often caused by DIY mods to the wiring) but it's also a potentially dangerous one. An open ring leaves two radials run using 27 A max cable (often derated now because of added insulation) protected by a 32 A MCB, which is really just an electrical fire waiting to happen if there's an overload on either side of the broken ring.

 

[Avendit]

The first one we had was designed to fit in a kitchen cabinet, but it only stored about 4 kWh, not really enough (enough for one shower plus a bit of hand washing). IIRC, I think our 9.5 - 10 kWh unit cost around £2k, so around double the cost of an equivalent capacity hot water cylinder. Its losses are only around 25% of those of a hot water cylinder, though, so it saves around 200 to 250 kWh/year in losses. It also fits in a very much smaller space, so, overall it's not bad value. The main disadvantage is the weight. Ours weighs something like 130kg, so it's not an easy thing to move around when installing it.

Having just recently done new heating system + heatpump, I wish something on the various sites I glanced at had more clearly articulated the advantages of the stores (they all said 'better', but none said how). I spent a very brief time looking at them, but couldn't immediately see the advantage over a cheap huge HW tank. Long term savings + size could have sold us TBH.

Our heating system's 50l buffer tank has a big 'C' rating on the side of it. So, I could see us replacing that once day, but I think the HW tank is there to stay.

Super informative thread overall tho, thanks all for contributions.

 

[ringi]

heating system's 50l buffer tank has a big 'C' rating on the side of it.

Remember the heat goes into your property that escapes from the bifffer tank, hence the C rating may not be an issue.

 

[Avendit]

Remember the heat goes into your property that escapes from the bifffer tank, hence the C rating may not be an issue.

It's out in the garage, so not that helpful :-(. I think it's quite a big surface area to volume, hence the problem.

Need to baseline the system this winter, see of we need to care really.