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    • CommentAuthorJohn Walsh
    • CommentTimeNov 12th 2021
     
    Been looking at timing E7 usage to when forecast carbon intensity is lowest by using data from the National Grid's region-based carbon intensity forecasting API.

    We currently have a Raspberry Pi controlling E7 electrics - 3kw immersion heater, 4x 225w u/floor mats and 2x 250w towel rails - on the basis of time (the E7 period) and temperatures such as water, house average, bathroom floors and outside. Usual setup: Python algorithms switch GPIOs which switch optically isolated relays which switch solid state switches for the devices.

    Data grab below (a simple python requests.get to the Grid's API) for the best/worst (to see what we're saving) time chunks in the E7 period for 90 minute time period (for the immersion heater) and 3 hour (for u/foor mats) for today, tomorrow and Sunday. gCO2 figures not great as we live in a region with a massive coal-fired power station but saving still to be made. It's fairly trivial to factor the data into our python algorithms - e.g. run the python script at 00:55 each day - hw cylinder is big enough for 2 days, so could not heat water if it's currently hot enough and the following day offers less carbon intensive electricity etc.

    I wonder what the gCO2 savings equate to in terms of extra insulation etc.? API here https://carbon-intensity.github.io/api-definitions/

    Friday 12th
    90 minute time chunk
    Low carbon av: 95 gCO2/KWh from 03:30
    high carbon av: 169 gCO2/KWh from 06:30

    3 hour time chunk
    Low carbon av: 98 gCO2/KWh from 02:00
    high carbon av: 141 gCO2/KWh from 05:00

    Saturday 13th
    90 minute time chunk
    Low carbon av: 127 gCO2/KWh from 01:00
    high carbon av: 184 gCO2/KWh from 06:30

    3 hour time chunk
    Low carbon av: 131 gCO2/KWh from 01:00
    high carbon av: 165 gCO2/KWh from 05:00

    Sunday 14th
    90 minute time chunk
    Low carbon av: 240 gCO2/KWh from 02:30
    high carbon av: 283 gCO2/KWh from 06:30

    3 hour time chunk
    Low carbon av: 243 gCO2/KWh from 02:00
    high carbon av: 271 gCO2/KWh from 05:00
    • CommentAuthorRobL
    • CommentTimeNov 12th 2021
     
    It's a good option for low carbon heating, especially people here who have insulated and still need some heat but don't want to burn stuff and can't justify a heatpump.

    Sunamp(12kWh) or Warmstone(100kWh) make larger well insulated products, that conceivably could charge overnight and be a gas-boiler replacement during the day. I appreciate there are individual E-7 heaters, but they always seem to leak heat hence be difficult/annoying in practice - are there any enhanced products using eg. VIP panels to improve this?
    The form factor of a traditional heater makes it awkward to improve on the thermal time constant though.

    Even cheap rate elec usually costs more than gas, but it's certainly greener now.
    • CommentAuthorEd Davies
    • CommentTimeNov 12th 2021 edited
     
    What matters, though, is not the average grid intensity but the marginal intensity: the gCO₂/kWh for each increment in electricity use. During the last week gas (CCGT) has been generating all the time, even in the middle of the night, and any increase in consumption has likely come from that and so its intensity should be what is considered.

    OTOH, there's been some use of coal during the day so avoiding daytime consumption is likely very helpful.

    I've said this so often in so many venues that I have a canned rant on the subject: https://edavies.me.uk/2016/07/grid-intensity/

    Attached graph from https://gridwatch.templar.co.uk/
      gridwatch.png
    • CommentAuthorJohn Walsh
    • CommentTimeNov 12th 2021
     
    Looks to me Ed that you're running a very fine magnifying glass very closely over one element. Would it help to maybe stand back and look at the bigger picture? Two very simple points:

    1. The new element in the picture is better forecasting and making more people aware of forecasting - if it's not windy tonight but will be tomorrow night, then if you can, it'll be better for all of us if you use electricity generated by wind power when it's windy.

    2. The more people think about climate change the better. No ifs or buts on this and if adapting electricity use to coincide with forecast low carbon generation is a way in to making better decisions elsewhere then that is only good for al of us.

    On the other hand, I did wonder what the blockage is on here re talking about carbon intensity - thanks for making that clear.
    •  
      CommentAuthordjh
    • CommentTimeNov 12th 2021
     
    Posted By: Ed DaviesWhat matters, though, is not the average grid intensity but the marginal intensity: the gCO₂/kWh for each increment in electricity use. During the last week gas (CCGT) has been generating all the time, even in the middle of the night, and any increase in consumption has likely come from that and so its intensity should be what is considered.

    OTOH, there's been some use of coal during the day so avoiding daytime consumption is likely very helpful.

    I get a worried feeling when I read this. I can see the logic but I can't help thinking there's something wrong with it, and I can't quite figure out what it is. Your rant is better, but imagine a hypothetical country:

    It has quite a lot of PV, though not quite enough to meet demand. It also has a lot of coal power, though again not enough to meet demand. It runs the coal power at night when there's no PV (or very little). It uses CCGT to meet marginal demand at all times.

    It's clear that the CCGT isn't the main factor. What really matters is whether it's daytime or night. (this is John's point 1 I think).

    Maybe the way to look at it is that when CCGT is ramped up for a new user, it doesn't supply that new user. The new output is added to the grid and everybody gets the same mix of CCGT and PV|coal but with slightly more CCGT than before. In real countries, it all depends on how the grid is connected and how the power flows of course.
    • CommentAuthorRobL
    • CommentTimeNov 12th 2021
     
    These guys say the current elec carbon intensity is 170g/kWh:
    https://electricityinfo.org/real-time-british-electricity-supply/
    But I also see we are using 33% CCGT gas, so presumably the "margin rate" is then at the gas rate (much higher)?

    I can see in the 5 days the gridwatch graph above covers that CCGT is always delivering something; presumably the marginal CO2/kwh rate is the same all the time as gas is the only dispatchable source in the mix - is there really no CO2 reason to displace electricity to over night then, is it purely a financial exercise due to the energy bidding procedure? I agree that the grid is imperfect - we could easily have turbines curtailed while CCGT is being used due to line overload. This suggests the marginal intensity is impenetrably difficult for an individual to calculate.

    I'm trying to wrap my head around the marginal rate as a useful concept, but it also seems to suggest I may as well keep burning gas directly rather than have a heatpump, and I struggle to believe that.
      Capture.JPG
    • CommentAuthorEd Davies
    • CommentTimeNov 12th 2021
     
    Posted By: djhIt's clear that the CCGT isn't the main factor.
    No, it's not clear. If you use an extra kWh of electricity in Hypothetica it'll cause 1 kWh's worth of extra emissions at the CCGT intensity whatever time of day you do it.

    We're moving towards a grid where it will matter when you use electricity. It's not simple for an outside observer to see whether we've go there yet - e.g., I pointed out that the CCGT generation didn't go to zero in the last week but it's not obvious whether that was because there wasn't enough nuclear, wind, hydro, etc, or because a bit of CCGT was needed as reserve and for spinning frequency stabilization. So, as John Walsh implies, it's good to get people trained to the idea. We just shouldn't kid ourselves that micro-managing current electricity use makes much difference or that electricity is somehow nearly CO₂ free if used at the right times.
    • CommentAuthorEd Davies
    • CommentTimeNov 12th 2021
     
    Posted By: RobLI'm trying to wrap my head around the marginal rate as a useful concept, but it also seems to suggest I may as well keep burning gas directly rather than have a heatpump, and I struggle to believe that.
    We need to distinguish short- and long-term decisions. In the short term, I don't think it matters much when you run your heat pump, though keeping out of the times when the grid was burning coal (daytimes this week) would be good.

    Longer term, putting in a heat pump rather than a gas boiler pushes expansion of electricity generation plant in general which will likely mostly be low carbon (wind and nuclear, mostly, in the UK) so will likely reduce the average grid intensity. In effect, there are short- and long-term grid intensities which may be very different even starting from the same mix.
    • CommentAuthorphiledge
    • CommentTimeNov 12th 2021
     
    Posted By: John WalshBeen looking at timing E7 usage to when forecast carbon intensity is lowest by using data from the National Grid's region-based carbon intensity forecasting API.


    Interested to know why would you use regional data when youre connected to a national grid?
  1.  
    The marginal intensity applies only to the marginal load: the last infinitesimal bit of load (in the derivative dCarbon/dLoad).

    If all the loads everywhere were all assigned the marginal intensity, then the total (integrated) intensity of all the loads, wouldn't match the total grid intensity of all the generators. The arithmetic just doesn't work.

    So clearly some of my household's loads are the marginal intensity bit, but most cannot be. It's hard to decide which, but I'd say that if a particular load (such as central heating) is a large proportion of my total consumption and is repeated for many hours per year, then it's not a marginal load. But if I were to occasionally use a fan heater to top up my central heating, that could be marginal.

    That's a bit subjective, so it might be better to stick with using average intensity: if we all shift some consumption to a time when the wind blows harder, then on average over the week the UK will burn gas instead of coal, and more wind farms can be built.

    (Edit to add: the marginal generator might be (pumped) hydro in Scotland, Wales or Norway. The intensity of pumped hydro is greater than that of the electricity it was pumped with)

    I don't like the regional boundaries in that NG analysis, they imply that using an extra kWh in NScotland is less damaging than using it in London, but overall it works out the same. Likewise "green" tariffs and "self consumed PV"
    • CommentAuthorEd Davies
    • CommentTimeNov 12th 2021
     
    Posted By: philedgeInterested to know why would you use regional data when youre connected to a national grid?
    Because transmission losses are not completely insignificant.

    The usually quoted figure for _grid_ [¹] transmission losses is, I think, 3% but that's for the usual situation where generation and consumption is mostly fairly close, a hundred miles or so at most. For, say, the north of Scotland I expect transmission losses to be more significant when its calm so the local wind farms aren't generating much and most of the electricity is being transmitted from quite a distance away but much less significant when it's windy and all the local grid and embedded wind farms are generating.

    [¹] There are additional and perhaps more significant losses in the distribution network.
  2.  
    Mmm, presently NG think the intensity in N Scotland is 4g/kWh and in London it is 136g/kWh, so 34x more impact. Don't think that's down to transmission losses, it's based on different mixes of generation assigned to each region. I can't run fan heaters guilt-free!
    • CommentAuthorEd Davies
    • CommentTimeNov 12th 2021
     
    Agree, that's vastly more than could be accounted for by transmission losses. Transmission could still be a factor, though, if any parts of the grid are at capacity.
    •  
      CommentAuthordjh
    • CommentTimeNov 12th 2021
     
    Posted By: Ed Davies
    Posted By: djhIt's clear that the CCGT isn't the main factor.
    No, it's not clear. If you use an extra kWh of electricity in Hypothetica it'll cause 1 kWh's worth of extra emissions at the CCGT intensity whatever time of day you do it.

    Yes but one can argue that those extra emissions should be shared between all users, not all allocated to the new user. What's the difference between somebody who starts heating his water when the last bit of PV is available and another person who starts one millisecond later? If the emissions become 'too high' then it's not sensible or fair that the last person in should be dumped off. The reality is that the emissions of the electricity I use vary over time, they're not fixed at whatever they were when I turned on my water heater.

    We need to distinguish short- and long-term decisions. In the short term, I don't think it matters much when you run your heat pump, though keeping out of the times when the grid was burning coal (daytimes this week) would be good.

    You're agreeing with me and disagreeing with your own stated position here. Burning coal doesn't matter to the marginal rate. And you're contradicting what you said about Hypothetica.
    • CommentAuthorRobL
    • CommentTimeNov 12th 2021
     
    I think the marginal term is related to saying "the plane is going anyway"... therefore my marginal impact of this particular flight is low. There's a bit of extra fuel required due to my extra mass, but that will be much smaller than dividing up the fuel used by the number of passengers. We here hopefully wouldn't apply this incremental logic to flying, even though strictly speaking you could? I'm sure we all know many people do though, or just don't care enough, but surely that is misguided - it assumes perfect knowledge - but at some point a new plane/wind turbine is operated/built due to these marginal actions.
    • CommentAuthorEd Davies
    • CommentTimeNov 12th 2021 edited
     
    Posted By: djhYes but one can argue that those extra emissions should be shared between all users, not all allocated to the new user.
    But we're not playing some sort of blame game here.

    The question is, does varying the time you use electricity make any difference to the total emissions from the grid, e.g., does is matter if John Walsh heats his hot water cylinder at 03:00 on Saturday morning or 03:00 on Sunday morning? Without JW the grid would run happily enough supplying people from a mix of sources with average intensities of, say, 150 and 250 gCO₂/kWh on each of those days. Perhaps he takes 3 kW for 2 hours on Saturday morning so the grid controllers have to turn up a CCGT power station (intensity 394 gCO₂/kWh) somewhere in the general area where he lives causing an extra 2 × 3 × 394 = 2.364 kg of CO₂ to be emitted. Or maybe he instead takes the same amount on Sunday causing exactly the same amount of extra emissions despite the average grid intensity being quite a bit higher.

    Posted By: djhBurning coal doesn't matter to the marginal rate.
    Obviously I'm assuming they've started burning coal because the CCGT is maxed out so coal is now the resource being dispatched to follow the load. Presumably that's rather simplistic, particularly on short time scales (seconds to minutes) but over a period of hours I'd guess it's reasonable. The point is that the intensity for coal during the day this week would likely have been what was setting the marginal intensity.
    •  
      CommentAuthordjh
    • CommentTimeNov 12th 2021
     
    Posted By: Ed DaviesObviously I'm assuming they've started burning coal because the CCGT is maxed out so coal is now the resource being dispatched to follow the load.

    AIUI coal is not dispatchable like that, so I'd assumed it wasn't.
    •  
      CommentAuthordjh
    • CommentTimeNov 12th 2021
     
    Posted By: Ed DaviesThe question is, does varying the time you use electricity make any difference to thetotalemissions from the grid

    Then answer as to whether A whose computer decides to start water heating at time T and whose water heating starts at time t+3dt (because the computer etc is slow) is guilty or is it B whose computer decides at time T+dt but which actually switches on at time t+2dt (because its a faster computer? I'll argue that whatever answer you give is wrong, because such questions aren't sensibly framed.

    What happens if I start water heating with CCGT marginal and then somebody else stops and we go to full renewable power? Who gets the credit?

    I think it does matter what time you use power in Hypothetica.
    • CommentAuthorEd Davies
    • CommentTimeNov 12th 2021
     
    Posted By: djhAIUI coal is not dispatchable like that, so I'd assumed it wasn't.
    Clearly it is at some time scale as they turn it on and off when needed so it would be unreasonable for me to push my argument that CCGT sets the marginal intensity too far. If JW had decided my argument that the short-term marginal rate is all that matters was completely true and decided to heat his water during the day this week then he'd have been contributing to the need for coal burning. In that sense coal is contributing to the marginal intensity, though on the timescale of hours, not minutes.

    Posted By: djhI'll argue that whatever answer you give is wrong, because such questions aren't sensibly framed.
    I agree, it's not a sensibly framed question. We're not in court trying to decide who is guilty of using electricity; we're discussing whether in the narrow circumstances of the current UK grid outside some times of peak consumption it makes much difference to total emissions when you use electricity.

    Posted By: djhWhat happens if I start water heating with CCGT marginal and then somebody else stops and we go to full renewable power?
    Very hypothetical as, AFAIK, we either never or very rarely go to full renewable power, at least grid wide. Still, in those circumstances you'd have started heating your water too soon to optimally minimize total emissions, presumably as a result of not having accurate predictions of of the future grid situation.
    • CommentAuthorjms452
    • CommentTimeNov 13th 2021
     
    Posted By: RobLI think the marginal term is related to saying "the plane is going anyway"... therefore my marginal impact of this particular flight is low. There's a bit of extra fuel required due to my extra mass, but that will be much smaller than dividing up the fuel used by the number of passengers. We here hopefully wouldn't apply this incremental logic to flying, even though strictly speaking you could? I'm sure we all know many people do though, or just don't care enough, but surely that is misguided - it assumes perfect knowledge - but at some point a new plane/wind turbine is operated/built due to these marginal actions.


    Nice analogy Rob.

    I'm very skeptical of marginal intensity as the primary metric as we live in a transient infrastructure world. If demand follows renewables it gives the confidence to build the right infrastructure for the future rather than for now.

    i.e.
    An argument based on marginal emissions is:
    1. We are always using some CCGTs so why bother sifting anything as the marginal difference is tiny.
    2. Demand doesn't follow renewables so we need to build more CCGTs rather than renewables.

    Alternative argument based on average emissions is:
    1. It's windy and average carbon intensity is low so lets use electricity to displace gas heating.
    2. Even when it's windy we still need to run CCGTs so we should build more wind turbines.
    • CommentAuthorJohn Walsh
    • CommentTimeNov 13th 2021 edited
     
    Posted By: philedgeInterested to know why would you use regional data when youre connected to a national grid?


    Good question not least as it has a large bearing on the usefulness or not of the 'marginal' distraction - it helps shift the discussion out of a theoretical rabbit hole and onto what we can actually do to contribute.

    I'm not sure of the exact technical detail here but assume it isn't the case that all electricity generated by all the different sources is simply dumped into one across-the-nation massive wire which we then all tap into. See this NG doc ...

    https://raw.githubusercontent.com/carbon-intensity/methodology/master/Regional%20Carbon%20Intensity%20Forecast%20Methodology.pdf

    "Estimating the carbon intensity of the electricity consumed in each region requires modelling the power flows between importing/exporting regions and the carbon intensity of those power flows ... it is then possible to calculate the carbon intensity of electricity in each region. If the region is exporting power, then that region consumes electricity equal to its carbon intensity of generation."

    I'm assuming (and happy to hear other explanations) this means that the grid is split into regions, it isn't one massive wire around the nation. Each region has it's own generating characteristics and hence it really matters that we're all more aware of carbon intensity where we live and take action accordingly.

    For example, here's data grabbed from the Grid's API for my postcode last night (as mentioned above, it's not that difficult to write a bit of code to do this):

    Saturday 13th

    90 minute duration
    Low carbon av: 138g CO2/KWh from 01:00
    High carbon av: 311g CO2/KWh from 06:30

    This date was factored into the algorithm for heating our hot water. It was a bit windy early last night and so there was lots of power available from the wind turbines off the East coast at Skegness, which meant that the Ratcliffe coal-eater wasn't used. We heated our water for 90 mins from 1:00 when the 'actual' carbon intensity of the electricity generated in our region and supplied to us was 44% of what it was by 6:30 in the morning.

    Along with the helpful thoughts from Rob and jms452 I hope that puts to bed the 'marginal' distraction and allows us all to instead think about and focus on doing things better ...
    •  
      CommentAuthordjh
    • CommentTimeNov 13th 2021
     
    Posted By: John WalshAlong with the helpful thoughts from Rob and jms452 I hope that puts to bed the 'marginal' distraction and allows us all to instead think about and focus on doing things better ...

    Indeed, and along those lines ...

    I use E7 power to heat my water in the winter, controlled by a cronjob, so I'd appreciate seeing the Python script you use to optimise the timing if possible?
    • CommentAuthorJonti
    • CommentTimeNov 14th 2021
     
    To me it is clear that the it is over all grid usage that is important not so much individual use. Yes it would be an ideas to prevent the usage of certain high intensity usage at peak times such as washing machines/tumble driers but I cannot see any way to significantly reduce the peak time usage and spread this out that will work.

    Is not reducing the external energy needs of buildings the way to go? Though of course this would need to be born by the tax payer as otherwise it would turn into those who can afford to doing it and saving money and those who can't being penalised.
    • CommentAuthorphiledge
    • CommentTimeNov 15th 2021
     
    Posted By: John Walsh
    I'm not sure of the exact technical detail here but assume it isn't the case that all electricity generated by all the different sources is simply dumped into one across-the-nation massive wire which we then all tap into.

    I'm assuming (and happy to hear other explanations) this means that the grid is split into regions, it isn't one massive wire around the nation. Each region has it's own generating characteristics and hence it really matters that we're all more aware of carbon intensity where we live and take action accordingly.

    Electricity from the large generators is all transmitted around the country via a >200kv "supergrid" which is why its the national grid. Theres a 600kv DC link from scotland landing in northwales a mile from me bringing up to 2.2GW primarily from Scottish windfarms to my doorstep and beyond, so the country is definitely all sharing the national generation mix we have from the principle generators.

    Theres lots of smaller generators that are connected into the lower voltage more local distribution networks but I think the bulk of our generation and hence emmisions is from the bigger generators and likely sourced from outside any single DNOs patch
  3.  
    +1
    Diagram here:
    https://data.nationalgrideso.com/backend/dataset/cf3cbc92-2d5d-4c2b-bd29-e11a21070b26/resource/bb6d6ec6-16d9-4be5-b32c-1a70c09fd871/download/network-diagram-ew.png

    With the increasing connections between UK, Norway, Netherlands, Belgium, Ireland, a time will come when we have to consider UK generation as part of the European continental generation mix. Which will make it even harder to define the marginal carbon intensity, or even the average intensity.
    • CommentAuthorJohn Walsh
    • CommentTimeNov 16th 2021 edited
     
    Posted By: djhI'd appreciate seeing the Python script you use to optimise the timing if possible?


    The below merely tests fetching data from the Grid's API. Integrating into my time-and-temperature based script then involves setting a new 'time period' for the day - i.e. the code is scattered around so might not easily make sense. Instead, the below is a rough and ready example (e.g. no error checking) which can be run from a command line. Not sure how this will display here and I don't claim to be a python purist, as you'll no doubt see ...

    EDIT: obvs it's lost the indenting - does it still make sense?

    #!/usr/bin/python

    #### best worst/carbon intensity forecasts for a postcode today and next 2 days in the E7 period
    #### and for time periods for each device - imh wants 90 min time-slot, mat wants 3 hrs
    #### in the E7 period, there are 14 x 30 min ESO forecasts. Find 60, 90, 120 etc. minute blocks of time
    #### i.e. 30 min = 14 x 1, 60 min = 13 x 2, 90 min = 12 x 3, 120 min = 11 x4, 150 = 10 x 5, 180 = 9 x 6, 240 = 7 x 8
    #### i.e. for 90 mins there are 12 (3 x 30 min) blocks in the E7 period
    #### duration_elements = [[14,1,'30 minute'],[13,2,'1 hour'],[12,3,'90 minute'],[11,4,'2 hour'],[9,6,'3 hour'],[7,8,'4 hour']]

    duration_elements = [[12,3,'90 minute'],[9,6,'3 hour']]

    import requests
    import json

    headers = {'Accept': 'application/json'}

    postcode = 'NG1' ## only first part of postcode

    import datetime
    today = datetime.date.today()
    today2 = today + datetime.timedelta(days=1)
    today3 = today + datetime.timedelta(days=2)
    forecast_days = [today,today2,today3]

    for f_days in forecast_days:
    print(f_days.strftime("%A %d"))

    time_from = str(f_days)
    time_to = str(f_days)
    ESO_data_duration_pcode = requests.get("https://api.carbonintensity.org.uk/regional/intensity/" + time_from + "T01:05Z/" + time_to + "T08:00Z/postcode/" + postcode +"", params={}, headers = headers)
    ESO_data_duration_pcode_j = json.loads(ESO_data_duration_pcode.text)

    n = 0
    while n < len(duration_elements):
    low_duration_start = 0
    low_carbon = 10000
    high_duration_start = 0
    high_carbon = 0

    print duration_elements[n][2],"duration"

    for a in range(duration_elements[n][0]):
    block_end = a+duration_elements[n][1]
    co2_total = 0
    block_start = ''
    for b in range(a,block_end):
    if (a == b):
    block_start = ESO_data_duration_pcode_j['data']['data'][b]['from']
    co2_total = co2_total + ESO_data_duration_pcode_j['data']['data'][b]['intensity']['forecast']
    if (co2_total < low_carbon):
    low_carbon = co2_total
    low_duration_start = block_start
    if (co2_total > high_carbon):
    high_carbon = co2_total
    high_duration_start = block_start

    print "Low carbon av: ",(low_carbon / duration_elements[n][1]),"gCO2/KWh from ",low_duration_start[11:-1]
    print "high carbon av:",(high_carbon / duration_elements[n][1]),"gCO2/KWh from ",high_duration_start[11:-1],"\n"
    n += 1

    exit()
    • CommentAuthorJohn Walsh
    • CommentTimeNov 16th 2021 edited
     
    Posted By: philedgethe country is definitely all sharing the national generation mix we have from the principle generators


    To be clear, the above statement is simply wrong: cf. interesting pockets of green-building-climate-change-denialism over on the 'CoP26 - what does the team think?' thread.

    Anyway, here's another powerful example of the value of carbon intensity forecasts.

    Instead of the usual "immersion heater on at 6:30 for 90 mins" using a standard timer, a carbon intensity aware algorithm knows there's enough hot water to cope with normal usage today and that tomorrow morning there's a low carbon intensity period in my region. The result - instead of 90 mins x 3KWh x 430gCO2/KWh from 6:30 to 8:00 this morning (the actual intensity just now), it'll be 90 mins x 3KWh x 127gCO2/KWh from 1:00 to 2:30 tomorrow morning (the forecast intensity).

    That's 0.57Kg of CO2 instead of 1.94Kg of CO2. How long before carbon intensity forecasts become a normal part of the local weather forecast after the evening news on TV?

    Carbon intensity data for East Midlands region from https://carbon-intensity.github.io/api-definitions/
    •  
      CommentAuthordjh
    • CommentTimeNov 16th 2021
     
    Posted By: John WalshEDIT: obvs it's lost the indenting - does it still make sense?

    Thanks very much for posting it. Perhaps it would be better to attach the file (Attachments / Browse... down below)? That way it will keep the formatting and we can be sure we have the loops in the right places. :bigsmile:
    • CommentAuthorJohn Walsh
    • CommentTimeNov 16th 2021 edited
     
    Posted By: djhPerhaps it would be better to attach the file


    Sorry, didn't think of that. Attached. NB Only tested on Python and 2.7.9 and 2.7.16

    Forum says "You are not allowed to upload (eso_data_test.py) the requested file type: text/x-python" so saved as .txt
    •  
      CommentAuthordjh
    • CommentTimeNov 16th 2021
     
    Perfect, thanks :bigsmile:
   
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