The real reason for the push-out of Smarty-pants meters?

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I recently had my time wasted trying to find the reason why an economy 7 (overnight) immersion heater wasn't heating the water overnight, and it concluded with the customer finding out that their smarty-pants electricity meter had 'tripped', and that all was well because the electricity supplier had reset the meter remotely. It confirmed a rumour that the Companies (the grid) could both turn on and turn off smarty-pants meters at will. This fact started a building site discussion on the future use of this 'technology', with logical arguments being made that, once the uptake of air source heat pumps (ASHPs) and electric cars are widespread then it follows that overnight electricity consumption will be significantly higher than daytime consumption in many residential areas; the argument being that 1 or 2 cars would be charged overnight per household at around 3kW each. Add to this the ASHP struggling to make the quoted heat outputs once external temperatures drop below 5 Celsius and we have a possibly common scenario of the ASHP also being on overnight, adding perhaps 6kW more to each household's load.

At this point the site sparkie interjected with a comment to the effect that the supply cables laid in the street are sized assuming each house consumes only 3kW (diversity, and all that), which raised the possibility of overheated supply cables burning out in many streets.

Would someone qualified to comment care to confirm or deny this 3kW claim?

If this is true I can see one method by which 'the Grid' could protect itself from the embarrassment and expense of repairing melted cables; they could remotely turn off a proportion of the supplies in the street with the hot cable...the result being that some residents may wake up to a cold house, no hot water, and a car that refused to take them (all the way) to work.
Perhaps this is truly one of the advantages of the smarty-pants electricity meter, just not one the customer would appreciate.

MM
 
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The smart-meters are not for the benefit of customers (despite the publicity claims). Rather, they enable the utility companies to ration/throttle demand at peak demand times and also to charge higher unit prices at peak times.
 
It confirmed a rumour that the Companies (the grid) could both turn on and turn off smarty-pants meters at will.
That feature exists, but isn't intended for or likely to be used for load shedding unless there was some unavoidable emergency.

The way that smart meters will be used for load shedding is that certain high load items such as ASHPs and EV charging will adjust their load (including being totally off if necessary) based on demand and availability.
This should have minimal impact, since homes do not instantly freeze if the heating output is reduced or even switched off for half an hour, and electric cars do not normally require the entire time they are parked to charge.
What matters is whether the car has sufficient charge for the following day - the actual rate of charge and the times it is charging are irrelevant.

supply cables laid in the street are sized assuming each house consumes only 3kW
ADMD is more usually 2kW, After Diversity Maximum Demand. It's what's used when designing supply networks to allow cables, transformers, switchgear and so on to be sized appropriately.
Even for properties with EV charging and heat pumps, the ADMD is surprisingly low. There is a typical calculator here: https://www.spenergynetworks.co.uk/pages/admd_calculator.aspx where you can enter your own values.

Add to this the ASHP struggling to make the quoted heat outputs once external temperatures drop below 5 Celsius
There is no 'struggling', most ASHPs work with outdoor temperatures down to -25C.
 
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Heat pumps can be a grid stabiliser.

Also, heat pumps are the often the most efficient way to use ANY source of energy to heat a building.

It makes more sense to burn gas in a power station to make electricity for heat pumps than to pipe gas to homes to burn for heat: A modern combined cycle gas powerplant is about 40% efficient after transmission losses, 10 megawatts of gas produces at the power plant 4 megawatts of electricity,

- Electric resistive heaters in homes would give you about 4 megawatts of heat

- Burning the gas in the houses would give you about 9 megawatts of heat (we are very good at getting energy out of fuel on site) - so seems rational to do this... BUT:

- Use that 4 megawatts of electricity in heat pumps @ COP 5 you end up operating at 200% efficiency, a 100% bonus. Literally more energy than the gas itself contains ends up being put into buildings. You only need COP 2.5 to break even with on-site fuel burning, and COP 6 units work in most environments.
 
Also, heat pumps are the often the most efficient way to use ANY source of energy to heat a building.

I think you are being too optimistic about how well heat pump systems perform.

An Air Sourced Heat Pump that is heating a cold swimming pool on a warm humid day will achieve a high COP

The same model heating a house on a cold winters day will not achieve anything like the same COP

A graph of COP plotted against external temperature would show how reliable heating would be in winter.

In the right location and the right type of house ASHP will work.

In 1979 we bought a plot of land to build our home on, at the time there was no gas supply so "alternative" electrical heating was on the agenda. With over a year to wait before we could start the build there was plenty of time to research heat pump systems. We had a babbling brook as our boundary so we had options of water source as well as air source.

The Philips Experimental House project at Aachen provided us with masses of data. Additional data came from a various sources such as NCAT ( now CAT ) at Machynlleth. These were actively promoting alternative methods of heating but at the same time also advising caution about the claims that were being made about systems such as ASHP

The conclusion was that air source heat pumping was excellent in summer for both supply of hot water and cooling of the house. What it could not guarantee was the adequate heating of the house in winter as evaporators ( the outdoor heat exchangers ) would be prone to icing up and would then require electrical heating to de-ice them.
 
I'm really not being optimistic at all, most environments they are installed in aren't cold enough for it to be an issue.

It's not the technologies fault that design and install can be poor in the UK - just like it is with boilers.

The UK still has latent thinking that ON OFF heating is best, when in reality very few houses in the UK need such a heating regimen.
 
The UK still has latent thinking that ON OFF heating is best, when in reality very few houses in the UK need such a heating regimen.

Most modern systems are not that simple these days - My gas boiler system modulates down as it approaches the set temperature and if the heat loss, is within it's modulation range, it will continue to generate heat, rather than switch off.
 
The ultimate aim of smart meters is to enable pay as you use , so money from your account as the power is used. This would require a change in consumer law though . The other benefit to companies is the loss of all meters reader jobs and the removal of estimated bills which consumers have no obligation to pay .
 
Wait until they charge you for reactive power like everywhere else.
 
What does that mean?
Smart meters can measure reactive power, at the moment I am not aware of any domestic charge for it - other countries have either a flat rate for domestic or other requirements.

What is Reactive Power and how is it measured?

Reactive Power (kVArh) is the difference between working power (active power, measured in kW) and total power consumed (apparent power, measured in kVA). Some electrical equipment used in industrial and commercial buildings requires an amount of ‘reactive power’ in addition to ‘active power’ in order to work effectively. Reactive power therefore generates the magnetic fields which are essential for inductive electrical equipment to operate, especially transformers and motors.

Power Factor is a term used to describe the relationship between ‘active’ and ‘reactive’ power; it denotes how effectively electrical power is being used:

• Bad power factor - is low (less than 0.95), indicating that more reactive power is required.

• Good power factor - is high (greater than 0.95) indicating that power is used more effectively.

• ‘Perfect’ power factor - (1.0) is known as unity and does not use any reactive power. Most electrical equipment, such as motors, compressors, welding sets and even fluorescent lighting, create an inductive load on the supply.

An inductive load requires a magnetic field to operate which then causes the electrical current to “lag” the voltage i.e. the current is not in phase with the voltage.

As more domestic installs get more complex and charging more detailed / streamlined local networks may have more of an interest in charging for this.
 
The place for power factor corrn is the appliance, though, surely? They can add capacitors ...
 
Smart meters can measure reactive power, at the moment I am not aware of any domestic charge for it - other countries have either a flat rate for domestic or other requirements.

What is Reactive Power and how is it measured?

Reactive Power (kVArh) is the difference between working power (active power, measured in kW) and total power consumed (apparent power, measured in kVA). Some electrical equipment used in industrial and commercial buildings requires an amount of ‘reactive power’ in addition to ‘active power’ in order to work effectively. Reactive power therefore generates the magnetic fields which are essential for inductive electrical equipment to operate, especially transformers and motors.

Power Factor is a term used to describe the relationship between ‘active’ and ‘reactive’ power; it denotes how effectively electrical power is being used:

• Bad power factor - is low (less than 0.95), indicating that more reactive power is required.

• Good power factor - is high (greater than 0.95) indicating that power is used more effectively.

• ‘Perfect’ power factor - (1.0) is known as unity and does not use any reactive power. Most electrical equipment, such as motors, compressors, welding sets and even fluorescent lighting, create an inductive load on the supply.

An inductive load requires a magnetic field to operate which then causes the electrical current to “lag” the voltage i.e. the current is not in phase with the voltage.

As more domestic installs get more complex and charging more detailed / streamlined local networks may have more of an interest in charging for this.
Still not got a clue sorry.

Ultimately I will be charged for what I use.
Smart meters monitor what I use.
I will pay the charge dependant upon the agreed charge per unit by my supplier.

All the rest is fluff and irrelevance. :rolleyes:
 
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