If you have a new account but are having problems posting or verifying your account, please email us on [email protected] for help. Thanks :)
Hello all! Please ensure that you are posting a new thread or question in the appropriate forum. The Feedback forum is overwhelmed with questions that are having to be moved elsewhere. If you need help to verify your account contact [email protected]
Please note that it is not permitted to have referral links posted in your signature. Keep these links contained in the appropriate forum. Thank you.

EV charging cost

  • 16-12-2022 4:56pm
    Registered Users Posts: 890 ✭✭✭

    I drive a RAV4 PHEV, as it stands today "temp -4 to 4 degrees centigrade" I find per 100km, using Petrol will cost about one Euro less than charging at home during day time, and if you charge at public charging point petrol will be few Euros cheaper per 100 km

    You only save money if you charge at home at night time

    Am I missing something here?

    Post edited by Ultimanemo on



  • Moderators, Society & Culture Moderators Posts: 37,739 Mod ✭✭✭✭Gumbo

    You’ll save at day night, but save significantly at night rate.

    Show the sums.

    L/km on petrol v kWh/km on ev.

  • Registered Users Posts: 20,958 ✭✭✭✭ELM327

    It's unlikely unless you have a really bad electricity tariff and are beside a cheap petrol station.

    I charge my EV from my 7c/kWh night rate. No petrol or diesel comes close.

  • Registered Users Posts: 4,439 ✭✭✭MojoMaker

    Fossil fuel range doesn't seem to fluctuate much between warmer and colder temps true, and battery range certainly does, but honestly you'd have to be on a savagely bad elec rate to see parity, even in winter.

    Stick up L/100kms and Kwhs/100kms to be sure.

  • Registered Users Posts: 1,820 ✭✭✭kanuseeme

    The L/100km might not be accurate, it might show the km traveled while driving on fuel and electricity, my own car is 1.6L/100km and 18,5 kWh/100 km, while fuel use is actually closer to 7L/100km, ideally, it would require driving around with no charging the battery for a while.

    OP should get a charge point to power his house if it is cheaper than charging at home during the day.

  • Registered Users Posts: 890 ✭✭✭Ultimanemo

    Today Petrol prices around 160c per litre

  • Advertisement
  • Registered Users Posts: 890 ✭✭✭Ultimanemo

  • Moderators Posts: 12,334 ✭✭✭✭Black_Knight

    Finally some numbers!

    So *you* will only save money if *you* charge at home at night rate. Full BEV drivers probably save on either day or night.

    Typically an ev would be consuming ~22kWh/100km in this weather. Less sometimes, more sometimes, but that's a pretty fair number to go by. That Phev is way less efficient than typical ev. 31.3kWh/100km is motorway driving in the wind and rain kinda efficiency

  • Registered Users Posts: 890 ✭✭✭Ultimanemo

    I used to get 18.0 to 19kWh/100km during the summer

  • Registered Users Posts: 890 ✭✭✭Ultimanemo

    I didn't mean public charging points are cheaper than home charger, may be I didn't phrase it correctly

  • Advertisement
  • Moderators, Society & Culture Moderators Posts: 37,739 Mod ✭✭✭✭Gumbo

    I did. That’s why 10 years ago, I swapped to EV.

  • Moderators, Society & Culture Moderators Posts: 37,739 Mod ✭✭✭✭Gumbo

  • Registered Users Posts: 890 ✭✭✭Ultimanemo

  • Registered Users Posts: 890 ✭✭✭Ultimanemo

    Their day time tariff is high, I don't like them anyway, they claim 100% renewable, how can you achieve that?

    They increased their tariff when gas prices went up even though the wind prices didn't go much higher

  • Registered Users Posts: 6,146 ✭✭✭crisco10

    Lots of suppliers (SSE, energia, BGE) claim 100% Green. Its only a paper exercise around generation credits. I wouldn't get too hung up on it.

    Re the exercise at hand, the EV efficiency seems really poor. Is that common to most PHEV? My BEV (ioniq 5) is easily about 22kwh/100km in this weather, 17.5 averaged annually.

    And doing the sums to calculate the "breakeven" price for electricity based on your numbers. For 1000km driven;

    ICE requires 66l at 1.60 = e105

    Ev requires 313kWh, if you spend e105 on 313kWh, that's a unit rate of 33c/kWh. So yeah, at 20c a unit, your saving about 35%, at 40c a unit it's more expensive.

    But I'll say again, that PHEV kWh consumption is bonkers. The same sum for a more reasonable consumption (20kWh/100) gives breakeven of more like 50c/Kwh.

    I wonder is the PHEV consumption so high because of preheating in this cold weather? With a relatively small battery, using it to heat the car for 0 distance covered is gonna skew things.

  • Registered Users Posts: 3,125 ✭✭✭Buddy Bubs

    My audi a6 was about 7 litres per 100kms long term average. At todays prices of 1.80 per litre that's 12.60 euro for 100kms. At over 2 euro a while back its about 15 euro.

    My day rate electricity after discounts is about 30c per kWh which is probably typical and cupra born is using 17kwh per 100kms since I got it so that's 5.10 euro for 100kms or about 40% of the diesel cost now.

    Some folk paying crazy low night rates of under 10c which brings it down to under 2 euro for 100kms or about 15% of my a6 diesel cost.

    I'm aware some diesels and even some petrol are more efficient than my a6 and could do 100kms for about 8 or 9 euro at 5 litres per 100kms. Still 4 times what people paying on night rate EVs.

    Hopefully both electricity and diesel/petrol costs come down in 2023.

  • Registered Users Posts: 890 ✭✭✭Ultimanemo

    Probably the weight of the engine, petrol tank and other components, besides RAV4 is SUV/cross

  • Registered Users Posts: 6,146 ✭✭✭crisco10

    I thought that too, but the petrol consumption isn't bonkers when bench marked against a similarly sized petrol only car. If it was purely down to that you'd expect both to be higher when benchmarked?

    And the Ioniq 5 BEV is hardly the most aerodynamic machine. Lol

  • Moderators Posts: 12,334 ✭✭✭✭Black_Knight

    Are your ev consumption figures based on 22km of ev driving? Based on the photo you supplied.

    Very narrow data to be working off of

  • Registered Users Posts: 500 ✭✭✭PaulJoseph22

    You have a PHEV and a diesel in your household as well?

  • Advertisement
  • Registered Users Posts: 890 ✭✭✭Ultimanemo

  • Registered Users Posts: 1,804 ✭✭✭joe1303l

    @ Buddy Bubs

    Given that a Cupra Born is the class equivalent of a VW Golf/Audi A3, it’s not exactly comparable with an Audi A6 ?

  • Registered Users Posts: 3,125 ✭✭✭Buddy Bubs

    No just highlighting the difference in costs of fuelling my current and past car.

    The A6 was a reasonably efficient 2.0tdi using 7 litres per 100kms but I also gave the maths on a more efficient 5 litre per 100kms car which I suppose a golf or A3 1.6tdi could achieve, still dearer than an EV.

  • Registered Users Posts: 281 ✭✭butrasgali

    I have the rav 4 plug in. On the top photo above(ultimanemos photo),it has the total average read out ..I can't seem to get a total average until the electric runs out. I must be missing something

  • Registered Users Posts: 20,958 ✭✭✭✭ELM327


    13c is available now. Still much cheaper than trying to run a heat engine and garner traction from 30% of the output.

  • Registered Users Posts: 129 ✭✭pron

    Running my numbers:

    2022 Leaf 40kWh : Charging at home on ESB Night Boost (~20c off peak 2300-0800, ~13c between 0200 and 0400) averaging 16.8 kWh/100km currently in the sub-zero temps commuting Airport to Sandyford on the M50 daily, occasionally through town instead depending on google maps advice.

    Majority of charging is done at the cheaper rate using a timer, which gives me about 13kWh overnight, which seems to more-or-less cover the commute.

    Diesel people carrier (Grand Picasso) getting about 6.6l / 100km long term average.

    Leaf 1000km at 13c/unit : -> 168 units rounds to €22

    Leaf 1000km at peak 44c/unit : -> 168 units rounds to €74

    Leaf 1000km at new eCars rate 56c/unit : -> 168 units rounds to €95

    Picasso 1000km at peak Diesel €2.20 litre : 66 litres €145

    Picasso 1000km at current Diesel €1.70 litre : €113

    [Edit to add eCars rate

    If diesel drops below €1.43/litre we hit the crossover point with eCars, but I can't see that happening soon]

  • Registered Users Posts: 4,439 ✭✭✭MojoMaker

    That's not a great D/N rate at all though. I'd be querying that with my provider as they can all do better.

  • Registered Users Posts: 8,316 ✭✭✭micks_address

    i charge at home between 2am and 4am on electric irelands 12 cent night boost.. i dont use the car a lot so its fine. I have free charging at work.. and solar/battery storage so i can store 9.5kwhs at 12 cents and use that to cover most of the day rate in the house and pay 20 cents for house loads 11pm to 8am (apart from the 2am cheap rate.. i usually run the dishwasher/washing machine those hours as well) public charging is not cheap now.. had to go to cork and back yesterday.. used ionity at 71 cent kw.. for 20 minutes (waste as it wasnt even giving me the expected rate of charge.. 60kwh versus 100 i expected as was in a hurry) - and esb for 41 cents kw in fermoy to add 50% charge for the trip back to dublin.. luckily i dont have to use public chargers often. Hoping to use excess solar in the summer months as well to charge.

  • Registered Users Posts: 886 ✭✭✭brownej

    For the charging rate calculations you really need to take into account the losses with charging which you dont have with fuel.

    Its usually around 10% difference between the amount of charge delivered to the car (i.e. that you pay for) vs what the battery stores.

    It changes the break even point a bit. If you HPC charge regularly the losses are higher.

    Currently for me it is cheaper to public charge than use my electricity rate. I need to change but have to be really careful about it. Its not all about the headline rate per kWh. The smart tarrifs and EV tarrifs have absolutely massive standing charges compared to the non smart tariffs. You really need to have a very good view of your usage profile. Unfortunately you cant see the data unless you have a smart tariff with your meter. Just having a smart meter is not enough. Mine seems to be busted anyway and the power companies dont give a crap. The need 6 estimates before they will send someone out and I will likely be charged if I request an engineer visit. You would think that if a smart meter isnt transmitting data back that they would send someone out automatically not wait a year for 6 estimated readings.

  • Advertisement
  • Registered Users Posts: 5,747 ✭✭✭kirving

    But full EV's carry around even heavier batteries and don't have that consumption per 100km.

    I think it's just that it's cold at the moment, and you're using battery (that would otherwise go to extend your range), to heat the car. If you pre-heat the car, using energy from the grid rather than the battery, you would still used the same amount of energy, but it might not show up as an increased kWhr/100km (it doesn't in my car at least).

    For reference, my 330e is under 20kWhr/100km consistently, and only about 200kg lighter.