Maximise off peak electric traffis

[Alexphd1]

Starting to look at electric tariffs for the new build and have came across the octopusgo tariff with 4 hours off peak per night which would suit as very well.  Any simple ideas/solution could I use to maximise the off peak

1. Run ASHP to recharge thermal store (possibly on higher temp?)

2. Use time delay for overnight usage on dish washer & washing machine

3. Charge EV 

4. Cheap mechanical timers on charging devices ie laptop, mobile phone etc

 

Missing anything? 

[ragg987]

If you have solar PV you might want to do those things in the daytime instead. No single right answer, for us the cheap tariffs would not save money.

 

Timer for mobile phone may not be worthwhile, do check how much power they consume over 24hrs compared to charging mobile over 2 or 3 hrs then switching off.

[Alexphd1]

You got a valid point with pv but I think we are going to use most of our PV (cut to 3.68kw at inverter) with our base load ie mvhr, hot water tap, fridges etc with any extra imersion dump for any excess pv. But with a 5p kwh off peak surely it would be worthwhile boosting thermal store (plenty of hot water for morning showers) etc with this? I need my mobile on 24/7 and usually charge it at night while sleeping. 

 

Edit. Just worked out how much to charge phone every night. Ditch that idea.

Edited July 2, 2019 by Alexphd1

[AliG]

This is very interesting, previously I looked at various economy 7 type tariffs and they were pointless as the higher daytime charge more than offset the lower night-time charge.

 

This tariff seems to have a low daytime charge so if a large amount fo your electricity usage is at night it will save you money. Having looked into it, only Octopus seems to be offering this, other suppliers continue to raise the daytime rate to the point where savings would only be likely if you could shift over 50% of your electricity usage to the nighttime rate.

 

I have tried tracking our usage over a day, we have an EV which accounts for around 20% of usage, we have 5 kW of PV, we have MVHR, we have a lot of dusk to dawn lights and the pool pump runs 24 hours a day. I reckon I could get around one third of my usage into that 4 hour period which would mean a massive saving with almost no effort on Octopus Go. Further savings could be made by delaying the dishwasher etc but this relies on the family making an effort.

 

As an aside when I just checked rates I could get gas for 2.65p per kWh and electricity for 14.1p, so electricity is currently over 5x the price of gas.

 

Now I have to figure out if I can get one of these tariffs on three phase, I have a smart meter, but it does not have a wireless module I believe.

 

Update-

Having looked into it the state of smart metering is still a bit of a mess, new SMETS2 meters which remain smart when you change supplier are just being implemented but are not available everywhere and from all suppliers, I suspect it will be early next year before this is resolved. I have emailed Octopus to ask them the situation.

 

Meanwhile I am going to switch tariff and save about £300 so that's good, I only set up the current one a few months ago, prices seem to have fallen recently.

 

Edited July 2, 2019 by AliG

[Jeremy Harris]

Octopus seem to be offering the "Go" tariff as a bit of a loss leader at the moment, as they have a strong vested interest in getting as many of their customers to have "smart" meters installed as possible.  Whether "Go" (or "Agile") remain so competitive once there is a critical mass of customers locked in with "smart" meters remains open for debate.  If I had to guess then I would say that these "smart" meter only tariffs may well stay competitive for 2 to 3 years, but are then likely to either rise, either because they aren't sustainable in the long term (they seem to be working with virtually no margin for profit at all right now) or because comparing prices with these variable tariffs will be very much harder.  The end result (which is probably what the suppliers want) is that customers will be less reluctant to change supplier in future, I suspect.

[ProDave]

Don't for one minute think all your PV generation is going to be used up by the fridge, mvhr etc.  I have the same, 4KW of panels, and a 3.68Kw inverter and I only just use 95% of what I generate by very deliberately using the things like washing machine, dishwasher, tumble dryer one at a time in the daytime. And a dump controller to send excess power to the immersion heater.

 

So in the summer you would barely be using any off peak. Would it be worth the extra standing charge and higher daytime rate?

 

Also if you are thinking of an ASHP think about using an unvented cylinder rather than a thermal store.  A thermal store needs water at a hotter temperature, which an ASHP is not going to do very well, if at all.

[Alexphd1]

Standing charge 25p and day rate 14.8p which is pretty good. 

 

Good point with the thermal store v UVC but with this system a thermal store better (log asification boiler)

 

Big house with pretty high base loads.

Edited July 2, 2019 by Alexphd1