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  1. There's a lot of variables, so YMMV but I've seen thermal clipping of discharge rate and mine is in an integrated garage. The installer groups are full of customers asking why they're importing from the grid when the battery has charge and usually the answer is the battery is too cold. If you have enough headroom in discharge rate then you'll never even notice - you'll probably never notice if the heater is keeping the battery warm either. It's just an inefficiency you can skip if you have space inside, but it's not the end of the world if outside is your only choice.
  2. Don't put it outside, charge/discharge rates will be crippled in cold weather or it'll use a resistance heater to avoid that issue, a waste of the stored energy.
  3. That's the one, the data is the same (daily average temperature) but that website lets you choose where to clip the area (at the "no heating required" point) which in this case represents HDD.
  4. Yes, lower heat loss so the base load of 1kW in the example holds the house at a higher temperature, meaning fewer HDD as they're calculated against the "no heating required" baseline.
  5. Did they specify a flow temp? They proposed ripping out and replacing all my rads to hit a flow temp of 50 and would not allow me to spec larger radiators at my own cost. I raised it with the heat pump team and greg@octopus who just referred it back to the heat pump team. They claim that they design for a scop of 3.3 with an "efficient" flow temp of 50 because 3.1 would cost the same to run as a gas boiler. This year the average Octopus tracker scop needed for price parity is around 3.7, so they're openly talking absolute nonsense. Quoted 5.5k after the 7.5k grant, so not even worth accepting then doing the rads myself later. I was on here touting them as a good option before I hit this brick wall with them.
  6. Octopus refused to design rads for a flow temperature below 50°C for me so they're a non-starter for homes that can (and should) go lower. Smaller local MCS outfit has been much more accommodating.
  7. I don't understand the price of these things, you could pay a human to do it for about four years for that, how long is the warranty?
  8. Yes, Vaillant I think use a MID approved electricity meter but the MID approved heat meters are very expensive so they use cheaper sensors to calculate flow rate and flow/return temp. Generally regarded as accurate enough, some other manufacturers have been shown to be way off.
  9. Arotherm plus? They're known for outperforming the datasheets when installed well. You're a bit above the crowd at https://heatpumpmonitor.org/ but it depends if your plumber was just rounding up and you will be running at a lower flow temp etc.
  10. The upgrades part of the site is for an ASHP Install quote, if you just want information from their articles try https://www.heatgeek.com/category/knowledge/ or their YouTube channel https://youtube.com/@HeatGeek
  11. I could be wrong, but I think this is the same change that has been in place for new signups since December, so if you signed up recently there won't be an extra increase. They're now moving old signups which weren't a fixed term tariff (which the new one is) to the new rates.
  12. Octopus Tracker has had by far the best rates over the last year. Obviously it's not without risk as prices change daily but as long as the market is on a downward trend it should be a winner.
  13. In hindsight, Cosy worked well but ended up costing £30 more than just being on Octopus Tracker for 3 months, before even factoring in battery inefficiencies. So I'm just on Tracker now. Obviously tracker won't stay cheaper forever, but at present with low rates on Tracker there just isn't a use case for Cosy to me. It still compares well against standard variable, of course. Flux was a different beast, over £200 better being on that over summer compared to Tracker with fixed export at 15p, so I'll switch back to that again in the spring depending on where export rates go.
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