Octopus go instead of economy 7 (storage heaters)

ForestBluebells

Looking at all the comparison sites I can’t find a cheaper tariff however I stumbled across octopus go on a social media post and that does actually seem cheaper, day rate the same as the cheapest tariff I could find (who are also not taking on new customers) and a lot cheaper than any other tariff I found plus the night rate is over half competitors. 

I don’t have an electric car but do have storage heaters and heat my hot water overnight using 64% overnight. 

How does it work with a 4 hour cheap rate in terms of my storage heaters. Will they automatically only be charged for the 4 hour night period or will they try and charge for the usual 7 hours from the economy 7 meter?

if I can ensure my dishwasher and water are used in the 4 hour window this will definitely work out best for me but I didn’t know how the storage heaters work?

[Deleted User]

The answer to your question depends to a degree on the internal wiring in your home. A lot of storage heaters are on their own timed 7 hour circuit.

A couple of things to bear in mind. Firstly, Octopus Go/Go Faster are time-of use tariffs which require a smart meter (this is where you may have wiring issues with your existing set up). The smart meter is set up to use a single register: there is no peak or off-peak. Your meter has also to be set up to record 30 minute usage in kWhs. Octopus pulls data from a smart meter once every 24 hours and the 48 by 30 minute data packets are used for billing. Everything that is using power during the cheap period is charged at the low rate. Your monthly statement comprises 31/30/28 days of detailed data based on usage and price for each 30 minute period.

ForestBluebells

[Deleted User] said:

The answer to your question depends to a degree on the internal wiring in your home. A lot of storage heaters are on their own timed 7 hour circuit.

A couple of things to bear in mind. Firstly, Octopus Go/Go Faster are time-of use tariffs which require a smart meter (this is where you may have wiring issues with your existing set up). The smart meter is set up to use a single register: there is no peak or off-peak. Your meter has also to be set up to record 30 minute usage in kWhs. Octopus pulls data from a smart meter once every 24 hours and the 48 by 30 minute data packets are used for billing. Everything that is using power during the cheap period is charged at the low rate. Your monthly statement comprises 31/30/28 days of detailed data based on usage and price for each 30 minute period.

I currently have a smart economy 7 meter which has 2 rates and shows day/night readings. I wasn’t sure how it works but I think my heaters connect directly to my night meter because when EDF installed my meter they didn’t connect my heaters up and they didn’t work for ages until someone came out and installed the meter properly 

QrizB

As a practical matter, your storage heaters will only store 4/7ths as much heat if run for 4 hours rather than 7. This might not be a problem in autumn and spring but in the depths of winter you might miss the extra heat. You'd be topping up at daytime rates (which might still work out cheaper over the year).

Looking at a typical storage heater, a Creda TSRE100 charges at 2200 watts. In 7 hours it would store 15.4kWh which would let it meet its rated output of 1kW from 0700-2225 (so all day). In 4 hours it would only charge 8.8kWh and would run from 0800-1645 (so it will be cold by teatime). Heating after that time would rely on the boost heater, if present (the Creda I linked to has one).

Other ToU tariffs to consider include:

• Octopus Go Faster offers 5 hours at 5.5p/kWh (rather than 4 hours at 5p/kWh) so you'd get 5/7ths of the stored heat and have less risk of running out.
• Green Energy Tide offers 7 hours at 7.5p/kWh but the day rate is a little higher than Go / Go Faster and there is an evening peak rate where the rate is over 30p/kWh.

It's your choice, really.

QrizB

Looking at energy costs, here's a very simple illustration.

Imagine a household that, over the whole year, uses 900kWh for each hour from 0000-0700 and 200kWh for each hour from 0800-2300. They will be using 6300kWh of E7 cheap rate and 3400kWh of day rate which is roughly the same split you give.

Let's also assume that they continue to use the same breakdown when they switch to a ToU tariff.

Taking the tariffs offered for my area (Southern) I get:

• Octopus Go (5px4h + 15.59px20h) = £1031/yr, average 11.66p/kWh
  
• Octopus Go Faster (5.5px5h + 15.59px19h) = £1058/yr, average 10.91p/kWh
  
• Grreen Energy Tide (7.5px7h + 16.44px13h + 32.55px4h) = £1160/yr, average 11.96p/kWh
  

Go Faster is cheapest despite using day-rate electricity to make up the missing 2 hours vs. E7. All three give an average p/kWh rate that beats any current flat-rate tariff I know of.

ForestBluebells

QrizB said:

Looking at energy costs, here's a very simple illustration.

Imagine a household that, over the whole year, uses 900kWh for each hour from 0000-0700 and 200kWh for each hour from 0800-2300. They will be using 6300kWh of E7 cheap rate and 3400kWh of day rate which is roughly the same split you give.

Let's also assume that they continue to use the same breakdown when they switch to a ToU tariff.

Taking the tariffs offered for my area (Southern) I get:

• Octopus Go (5px4h + 15.59px20h) = £1031/yr, average 11.66p/kWh
  
• Octopus Go Faster (5.5px5h + 15.59px19h) = £1058/yr, average 10.91p/kWh
  
• Grreen Energy Tide (7.5px7h + 16.44px13h + 32.55px4h) = £1160/yr, average 11.96p/kWh
  

Go Faster is cheapest despite using day-rate electricity to make up the missing 2 hours vs. E7. All three give an average p/kWh rate that beats any current flat-rate tariff I know of.

That’s amazing thank you. I’ll sign up to go faster. I can put my hot water on in the cheap hours too and dishwasher etc

QrizB

Do check first that your NSHs will be happy! There will be something that switches your NSHs on and off to align with the current E7 hours and this might not carry on working if you switch to Go Faster.

Depending on exactly how they are wired you might need to get an electrician in to make some changes to your distribution board.

Others have said that Octopus have a decent smart metering team; a message to them might clear this up.

[Deleted User]

ForestBluebells said

That’s amazing thank you. I’ll sign up to go faster. I can put my hot water on in the cheap hours too and dishwasher etc

There is no switching process for Go Faster as it is by invitation only. You will need a smart meter on 30 minute usage. To apply, email agile@octopus.energy

As I said earlier, and others have repeated, you need to check whether your NSH wiring is suitable for a single rate meter.