Electric Boilers & ErP Rating Explained - Climastar

Electric Boilers & ErP Rating Explained

Electric Boilers & ErP Rating Explained

All boilers have an ErP (Energy related Products Directive) rating that aims for a clear indicator of how efficiently it will run. This varies from A down to G.

We’ve all seen this as a visual stuck to the front of our appliances, and chances are we feel good about seeing our appliance nearing the greener ratings at the top.

This gives us also some preconception that we’re doing our bit to conserve energy and the more efficient the appliance; the more we will save on our power consumption.

The problem with preconceptions is, they’re rarely ever explained or given rationale.

Preconceptions become rumour, and rumour becomes (quite dangerously) adopted as fact. “Someone said so, so it must be true” et al.

A common phrase of my parent’s generation resonates here:

“It says ‘oxo’ on buses. It doesn’t mean they sell them”.

Electric Boiler & ErP Rating Explained

We only have to look at the ErP rating diagram above to think in polarising ways such as “Green = Good”, “Red = Bad” and “Amber” being the bit somewhere in the middle that’s somehow comparable to sitting at the traffic lights. But are we really getting anywhere?

This may be a little difficult to take, but it isn’t always that clear cut.

The road to understanding energy efficiency isn’t always a straight line either.

Balancing the equation

Comparing the efficiency of electric, gas and oil boilers side-by-side can be challenging. Despite being 99-100% efficient, electric boilers tend to have an ErP rating of D. Is that really fair?

On the other hand, all condensing gas and oil boilers must reach a minimum efficiency level of 92%, yet this is enough to award them an ErP A-rating.

When looking at gas boilers, you’ll see they’re pretty much all A-rated, while electric boilers tend to be D-rated.

There are a couple of reasons for this:

The reason for electric boilers having a low ErP rating is down to electricity being considered carbon intensive.

This is due to the power generation process which, in the UK (at least at the time of writing) is mostly done using fossil fuels.

While an electric boiler can heat water with little to no heat loss, giving the unit a 99-100% efficiency, the fuel factor sees the ErP rating appear low. Yet it’s not the boiler’s fault, the engineering gone into it’s design and construction, or it’s manufacture.

It’s because the electricity generation back at the power station produces high volumes of carbon.

(Live: Distribution of power generation sources in the UK – provided by energy dashboard)

Energy, or Political Sources?

It may seem on the face of it, that the manufacturers were being penalised for their production of electric boilers in this way. However, manufacturers don’t really have much control over where their customers will get their energy sources.

Previously, the majority of electricity generation in the UK was done with fossil fuels –  a process that can emit twice as much carbon as natural gas.

Electric Boiler & ErP Rating Explained

The reason the electric boiler (in this case the Climastar Stromboli) has such a high efficiency rating is because little to no energy is lost during operation. (0.02%)

Gas and oil boilers can’t match electric boilers in terms of energy efficiency, as they very rarely achieve an efficiency above 93%.

Where does the remaining 7% go? Not all 7’s are lucky.

7% of the fuel being used by these gas and oil boilers is being wasted, which means that for every £100 spent on heating the home, £7 is lost.

According to Plumr.co.uk, the average spend per month heating a house is (at present time of writing) up to £500 per month. Looking at that in terms of the above energy loss – that’s £35 per month (or £420 per year!) wasted.

That could be a week or a weekend break away somewhere, or money put to one side for a rainy day. You could even use this saving towards upgrading your heating system so that such wastage never occurs again.

In terms of energy efficiency, the electric boiler is the outright leader; yet the ErP rating is much lower – which is why comparing electric boilers with gas and oil units can get confusing.

We’re not just trying to compare peaches with apples – we’re also comparing the garden that grows them; and what someone else thinks of that.

How is electricity generated?

In the UK, electricity is generated in a number of ways to ensure that there’s a constant supply, including:

  • Fossil fuels
  • Nuclear
  • Renewables
  • Imports (the UK electricity network is connected to networks in Ireland, France and the Netherlands which can be used to import and export electricity as and when necessary)

The vast majority of UK electricity generation previously came from fossil fuels, which not only has a negative impact on the environment, but is becoming increasingly expensive.

This goes some way to explaining the low efficiency ratings of electric boilers.

It’s not really an indication of the efficiency of the boiler itself, but rather shifts bias toward where it’s electricity is coming from.

For more information on the Climastar range of boilers, please visit our boilers page.

Alternatively if you’d like to book a free Home Heating Survey with one of our electric heating consultants to discuss electric boilers in further depth – please click the following button.Request a Survey

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