Confused choosing a tariff for solar and batteries

Waynieoaks Forumite Posts: 3
Fifth Anniversary First Post Combo Breaker

I recently got solar and batteries with the intention of charging the battery overnight to use during the day. We are a high energy use house and while we try to be more efficient decided solar and batteries would also help us reduce demand on the grid. 

Having moved from Bulb to Octopus, I am currently on the flexible which costs 38.63p day and 16.21p night. 
They have offered me the loyal 12 month (with exit fee) at a cheaper day/night rate 36.12p/15.15p

Obviously I looked at the feed in tariff and that is where it does not make sense to me. The night rate is the highest of the three (18.43p) while the day (when I am trying to be off grid) is the cheapest 30.72p. Evenings are 43.01p to encourage you to get off the grid. I get that I would get money back on any export but my priority is own use and I don't think we will have much to export. But with my basic maths, I don't see the benefit of feed in (for us) and think it will be more expensive in the long run. 

Am I missing something? 


  • Dolor
    Dolor Forumite Posts: 7,563
    1,000 Posts Third Anniversary Name Dropper
    Have a look at Flux and E7.
  • DougMLancs
    DougMLancs Forumite Posts: 200
    100 Posts First Anniversary Photogenic Name Dropper
    edited 10 August at 11:38AM
    What size is your array/batteries and what aspect is causing high usage? Elec showers, heating, EV, heat pump? Your usage pattern will determine how much you can actually self consume. The battery will only store so much. Between May and September you’re highly likely to be exporting more than you think. Between June and now I’ve earned £210 from export on flux. If the DNO would’ve been quicker I could’ve included May and made £360. Also only used 12.5kWh from the grid in 3 months and that was for the battery calibration on commissioning.
    4.44kW SW Facing in-roof array with 3.6kW Givenergy Gen 2 Hybrid inverter and 9.5kWh Givenergy battery. 9kW Panasonic Aquarea L (R290) ASHP. #gasfree since July ‘23
  • Waynieoaks
    Waynieoaks Forumite Posts: 3
    Fifth Anniversary First Post Combo Breaker
    Thank you both... 

    It was Flux that was confusing me - but I guess the price is higher to encourage more export than import. 

    So I have an array of 2.84kWp as that is all we could fit and 9.6kWh worth of batteries with the plan of night charging as well as solar. 

    We were using 18-20kWh a day mainly with the use of my computers / monitors / servers etc.

    This is all newly fitted and because it is summer it is performing better making it hard to average - for example yesterday we used 17,48kWh of which 11 was self sufficient. Monday, we used 20 and only generated 5

    I shut everything down when not in use and have smart plugs in the office to power everything down so not on standby when not in use - am trying to be better with efficiency but can't do much without just not using the equipment. 

    Some days I will be working during the day and evening, others it is only evenings. 

    Usual couple of spikes in the evening with the cooker, or at night with the washing machine that we can schedule better.  
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