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National Grid can tell you when to use your washing machine – 48 hours in advance

September 26, 2017

By Paul Homewood



h/t Patsy Lacey



Another reason not to have a smart meter!




National Grid will be able to tell people the cheapest time to turn on a washing machine up to two days in advance.


New software, developed with conservation charity WWF, breaks the day down into two-hour segments, warning users when energy is at peak demand and informing them when demand is low.

It combines historical data from the grid with weather information from the Met Office to predict times of high and low demand.

The National Grid said it expected energy companies to use the information to produce their own apps encouraging customers to use energy when demand was at its lowest and turn appliances off when there was pressure on the system.


The data, verified by experts from Oxford University, also shows when low-carbon energy sources are active, allowing environmentally-conscious households to use energy at the best times for solar and wind energy.

Duncan Burt, director of the system operator at National Grid, said: “We’re providing our forecast data in a format that allows technology companies to build innovative apps and software that could make a real difference to how and when people use energy.

“Clear and concise information that can tell you in advance when’s best to turn on the washing machine, load the dishwasher or charge your car for example, is a step in the right direction towards a low carbon future. 

“This technology puts people at the heart of it, helping everyone to use power when it’s greenest, and likely, more cost efficient.”

In the future the system is likely to be most useful to electric-car owners, who can choose to charge their vehicle at the cheapest and most efficient time.

Some suppliers have started to offer “time-of-use” tariffs, enabled by smart meters, which reward householders for using energy when demand is low.


In January Green Energy UK launched its TIDE tariff which charges less per kWh at low-usage times, such as overnight.

British Gas’s long-standing Economy 7 and Economy 10 tariffs also charge users less for energy used at night.

The National Grid also said that 2017 had been the “greenest summer ever”. Between June 21 and September 22, 52 per cent of electricity demand was met by “low-carbon” sources, compared to 35 per cent four years ago.

Gareth Redmond-King, head of climate and energy at WWF, said the development was a “great leap forward” towards more renewable energy use.

“Green energy forecasting could be a game changer – making the connection between the weather and energy and helping people use electricity when it’s greenest.

“This is not just good news for reducing the effects of climate change but could also help us cut our home energy bills and it’s vital the UK Government bring in time of use tariffs quickly to maximise these opportunities,” he said.



At the end of the day (or night!), the total cost of electricity will still be the same. Interestingly, at the time, the Telegraph reported this on the TIDE tariff mentioned above:



The cheapest electricity will be available between 11pm and 6am every night, at 4.99p per unit.

The most expensive period will be between 4pm and 9pm on weeknights, when electricity will cost 24.99p per unit. This is the period when demand for energy spikes.

The average price for energy is around 14p per unit, according to consultants the Energy Saving Trust.

On the Green Energy UK plan, a customer who uses 30pc of their electricity at the cheapest time and only 2pc at the most expensive time would spend £891.25 on electricity each year.

But if the same customer used 2pc of their electricity between  at the cheapest time and 30pc at the most expensive time, their bill would be £1,063.13.

In both cases the rest of the usage would be 24pc used during the day, and 16pc used later in the evening.

According to price comparison site UK Power, the cheapest available annual bill for a medium-sized house is £871. 


So, even if you use 30% of your power at night, you’re still no better off. And if you don’t, you’re shafted!

  1. Patsy Lacey permalink
    September 26, 2017 4:07 pm

    Until recently we had an economy 7 meter. EDF offered a reduction in tariff by removing the economy 7 because our usage was out of balance in that we use far more electricity in the day – we are both retired. All our washing, drying and dish washing was done at night but it still was not enough to be economic. EDF were not the slightest bit concerned at offering a reduction by moving us away from the most environmentally friendly tariff. We haven’t got a smart meter and have no intention of having oine

  2. September 26, 2017 4:13 pm

    Tip : BBC hyped “Greenest summer” ever from WEF

    As does the Times on page 10 among with a Webster Little Emily article “First subsidy free solar farm”

    Note the strange wording
    “Can generate 16MW.. 10 from solar 6 from batteries”

    “Clayhill is expected to receiv payments for helping to balance the grid”
    Bet that is in effect a subsidy
    Like Hornsea2 the trick is that it is piggy backing on the back if infrastructure paid for by a megasubsidised existing farm next door
    Report quotes Richard Black

    Times bottom editorial also waxes lyrical

  3. Ian Magness permalink
    September 26, 2017 4:19 pm

    What a load of RUBBISH! How many people have the ability, or even the desire, to control the exact time of their energy use? Try telling a mother of babies and toddlers when the washing machine can be turned on, and when it shouldn’t be.
    When all the climate hype is seen as the fraud that it has become, and the energy companies no longer see the need to grovel before the green blob, watch suppliers break ranks and offer the cheapest energy from whichever sources (ie non-renewable) they can get it from.

  4. Joe Public permalink
    September 26, 2017 4:29 pm

    “The data, verified by experts from Oxford University, also shows when low-carbon energy sources are active, allowing environmentally-conscious households to use energy at the best times for solar and wind energy.

    But, but, but ,,,,,,,

    The gullible have already salved their consciences & virtue-signalled by opting for one of the so-called “100%-renewable” tariffs, haven’t they?

    • Gerry, England permalink
      September 27, 2017 12:50 pm

      For a laugh I got a quote for one and it £400 more than what I was one. More interesting was that once I had finally found the actual tariff as opposed to using their calculator, the cost was even higher!

  5. September 26, 2017 4:49 pm

    On twitter someone commented on the idiocy of being told to use your tumble drier when the weather is sunny and windy – exactly when you don’t need to use your tumble drier!

  6. Max Sawyer permalink
    September 26, 2017 5:08 pm

    How long before we are not allowed to use our electrical appliances when we choose?
    Remotely-controlled rationing?

    • September 26, 2017 6:15 pm

      No, no, terrible terminology – it’s now known as ‘demand management’ 😉

    • Joe Public permalink
      September 26, 2017 6:53 pm

      Nothing that crude.

      You’ll be *allowed* to use them at any time; just be prepared to pay a punitive penalty-cost.

      >100kW electricity users in UK have had that for decades; it’s called Maximum Demand Charges.

      Your Smart Meter will know your peak 1/2-hour’s demand, and *all* electricity consumption kWh that month may be based upon *that* peak.

      It’s a revenue-generator for ‘leccy companies.

  7. September 26, 2017 5:37 pm

    ‘warning users when energy is at peak demand and informing them when demand is low’

    So when they all pile in at the cheapest rate and time, demand will shoot up.

  8. September 26, 2017 6:54 pm

    Having worked in the nuclear industry, as far as I am concerned, I am happy to use baseload electricity whenever i want it. The cost of baseload generation is constant.

  9. Steve Gledhill permalink
    September 26, 2017 9:14 pm

    This morning Roger Harabin said on the BBC Today programme that the new system of forecasting would let us know when it would be sunny and/or windy so we’d know when electricity would be cheapest so we could use our power hungry tumble dryers. Surely windy and sunny are exactly the right conditions to hang the washing on the line … at no cost!

    • Gerry, England permalink
      September 27, 2017 12:51 pm

      Having an accurate weather forecast would help too!

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