Off-Peak Smart metering

Starbuckle

Despite what some may have convinced themselves, efficiency is not a red herring by any means.
The daily standing charge for gas is typically 34 pence, which totals approximately £124. annually, regardless if used or not.  The annual servicing cost for a gas combi-boiler ranges from £60 to £100+ (depending where you live) and is expected to increase.  Additionally, breakdowns are common due to the numerous components in a gas combi-boiler, which endure constant wear and tear. While thermal batteries may have a higher initial cost, they require significantly less maintenance over time and can store energy gathered during off-peak hours. Furthermore, they are considerably more efficient, and this efficiency is not merely a superficial concern.  I know two gas fitters who have transitioned away from gas, which is quite telling.

The UK government, despite Trump's attempts to dictate with calls to 'drill baby drill' for the benefit of the U.S, is committing to SMR's across the UK.
The future is electric!

Newbie_John

Putting unrelated politics aside.

By thermal batteries you mean storage heaters? They cost about £1000 and are good if you're on old school E7/E10 tarrif but.. it increases your day price.
So all depends on size of your house, EPC rating, times you at home.

For comparison these are the rates available to me on normal / E7 tarrif:
gas: 6p
electricity: 24p
electricity E7 night: 13p
electricty E7 day: 31p

Gas is 4x cheaper than electricity (standard rate) - but yes additional standing charge and maintenace costs can have significance if you a low user.

With a smart meter and Octopus Cosy you can really avoid "storing heat" because you have cheap electricity during the day 13-16 and run something that can be automatically controlled for example:
Philips 5000 Series Tower Fan Heater, 2000W - costs £90 on Amazon (but the price drops to as low as £60), you can set the heating periods on the app to match your ToU tarrif (not as safe as storage heater if you have kids/pets).

Also worth adding that every electric heater uses the same amount of energy - storage heater, electric rad, infra red, it all depends on use case.

The only exception is heat pump - it can provide you with 4x more heat from the same amount of energy consumed - but it comes with high installation cost. And heating air-cons which now don't require planning permission and are much cheaper.

There is so many factors to consider really, that's why there isn't one answer for all.

QrizB

Starbuckle said:

Despite what some may have convinced themselves, efficiency is not a red herring by any means.
The daily standing charge for gas is typically 34 pence, which totals approximately £124. annually, regardless if used or not.  The annual servicing cost for a gas combi-boiler ranges from £60 to £100+ (depending where you live) and is expected to increase.

I'm with you this far.

Starbuckle said:

Additionally, breakdowns are common due to the numerous components in a gas combi-boiler, which endure constant wear and tear. 

I would suggest that most gas combi owners wouldn't expect more than one repair a decade. But if that repair costs £400 (link), it'll be £40 a year pro-rata.

So we're up to £124 SC + £100 service + £40 repairs per year, which is £264 a year.

Starbuckle said:

While thermal batteries may have a higher initial cost ...

A Sunamp 150 ePlus is about £1500. That's about twice the price as new gas boiler (link) and 3x the price of a E7 hot water cylinder (link).

Starbuckle said:

... they require significantly less maintenance over time and can store energy gathered during off-peak hours.

We've discussed gas boiler maintenance above. An E7 water tank needs virtually no maintenance.

And the cheap-rate electricity needs a time-of-use (ToU) tariff, which brings us back to the topic of this thread. Otherwise you're paying 25p/kWh.

Starbuckle said:

Furthermore, they are considerably more efficient, and this efficiency is not merely a superficial concern.

Efficiency is one of those flexible words.

Yes, your thermal store will be more efficient at turning electricity into hot water than a gas boiler is at turning gas into hot water. Your Sunamp is close to 100% efficient (more on this later) while your boiler might be 80% efficient. However, an 80% efficient boiler burning gas at 6p/kWh will cost 7.5p/kWh of heat delivered. Meawhile your Sunamp will cost 25p/kWh, unless you move to a ToU tariff.

An E7 hot water tank, on the other hand, is also close to 100% efficient. Where they differ is standing heat loss. Per the Sunamp data sheet, the 150 ePlus loses 0.64kWh of heat per day. The E7 tank linked above loses 1.64kWh a day. That's 25p a day, £90 a year. It'll take more than a decade before the cumulatve cost of the extra heat loss equals the extra cost of a Sunamp.

Starbuckle said:

The UK government, despite Trump's attempts to dictate with calls to 'drill baby drill' for the benefit of the U.S, is committing to SMR's across the UK.

While I agree that we should electrify heat and stop burning stuff, I would be shocked if we see a SMR supplying electricity in the UK within a decade.
So here's your quandary. You've got a fancy stored heat system for hot water, which really needs a ToU electricity tariff for you to see most of the promised gains. This would be great if it was paired with stored heat for space heating; in other words, storage heaters.

But you don't have storage heaters, you have infra-red panels.

So do you switch to a ToU tariff, save money on your water heating but face paying 30p+/kWh for your space heating? Or do you stick with a flat-rate tariff and miss out on those cost savings?

I can't answer that question for you.

Starbuckle

QrizB, I appreciate your insights, but I feel it's important to address a few critical points regarding the efficiency and reliability of gas combi-boilers compared to thermal batteries.

Efficiency and Maintenance,

While you mention that gas combi-boilers can achieve around 80% efficiency that is very debatable, this figure is contingent upon regular maintenance and servicing. In my experience, many homeowners neglect this crucial aspect, leading to a decline in efficiency over time.  Additionally, once a gas combi-boiler surpasses 4 or 5 years old, its efficiency often drops well below that 80% mark due to wear and tear.  This decline can significantly impact energy costs and overall performance.

 Frequency of Repairs,

Moreover, I would argue that repairs for gas combi-boilers can be more frequent than you might expect. It's not uncommon for homeowners to face multiple repairs over a decade, especially as the system ages.  Each repair can be costly, and when you factor in the potential for unexpected breakdowns, the financial burden can add up quickly. 

Long-Term Cost Considerations

When we consider the cumulative costs associated with gas systems — annual servicing, potential repairs, and declining efficiency — the total can become quite substantial. This is why I emphaside the long-term savings associated with thermal batteries. While the initial investment may be higher, the reduced maintenance and the efficiency of converting electricity to heat can lead to significant savings over time.

The Future of Heating 

As we look towards the future, the transition to electric heating solutions is not just a trend; it's a necessary step for sustainability. The government's commitment to electrifying heat aligns with the need to move away from fossil fuels, making thermal batteries, and heat pumps, a more viable option in the long run.

I understand that the decision to switch to a thermal battery involves weighing various factors, including the need for a time-of-use (ToU) tariff.  However, I believe that considering the broader implications of our energy choices is essential.  What are your thoughts on the reliability and efficiency of gas combi-boilers as they age, QrizB?

I know quite a few plumbing and heating tradesmen and they all seem to believe gas combi-boilers diminish in efficiency fairly early in the journey.

QrizB

Starbuckle said:

What are your thoughts on the reliability and efficiency of gas combi-boilers as they age, QrizB?

My boiler is a regular (heat-only) model with a hot water storage tank. I do however know several people (friends, relatives and workmates) with combi boilers of varying ages and I don't recall any of them having any significant trouble with them in the past decade.

My regular boiler is around 20 years old and hasn't required any repairs yet. In the wider central heating system I have replaced the circulating pump once and the three-way valve actuator once. These are both straightforward DIY jobs and the parts are relatively cheap.

Starbuckle said:

I know quite a few plumbing and heating tradesmen and they all seem to believe gas combi-boilers diminish in efficiency fairly early in the journey.

Efficiency is difficult (almost impossible) to measure accurately without a heat meter, which is not normally fited to gas boilers. This leads me to wonder just how these people you mention have reached their conclusions.

Starbuckle

QrizB said

Efficiency is difficult (almost impossible) to measure accurately without a heat meter, which is not normally fited to gas boilers. This leads me to wonder just how these people you mention have reached their conclusions.

QrizB, I appreciate your response, but I need to address a few important points about measuring efficiency and the reliability of gas combi-boilers.

Measuring Efficiency

While it's true that accurately measuring efficiency can be difficult without a heat meter, there are established methods and industry standards for estimating gas boiler efficiency.  Manufacturers provide efficiency ratings based on standardised tests, and although real-world performance may vary, these ratings offer a reliable baseline.

Real-World Performance

Even if we accept the idea that efficiency is "almost impossible" to measure it doesn't change the fact that many homeowners report a decline in performance as their gas combi-boilers age. Even without precise heat meters, users can notice higher energy bills and less effective heating, which clearly indicate a drop in efficiency.

Maintenance Neglect

As I mentioned earlier, the efficiency of a gas combi-boiler heavily depends on regular maintenance.  Many homeowners overlook this crucial aspect, leading to decreased performance over time.  This is a widespread issue that contributes to the perception that gas boilers are less efficient than they should be.

The Bigger Picture

Ultimately, while accurate measurement is important, we cannot ignore the broader context of maintenance, age, and user experience. The cumulative costs associated with gas combi-boilers—servicing, repairs, and declining efficiency - paint a clear picture of their long-term viability compared to thermal batteries.

Your Perspective, may be that your aged boiler is in good shape, but you may have just got used to it.

I understand you may have doubts about the conclusions drawn by others regarding gas boiler efficiency. However, I encourage you to consider that the observations made by tradesmen in the plumbing and heating industry are indeed valid. These professionals, who I know personally, have extensive experience and firsthand knowledge of how gas combi-boilers perform over time. Their insights are based on real-world interactions with numerous systems and customers, making their observations significant. Ignoring their expertise undermines the practical knowledge they bring to the discussion.

Respectfully, I can see you are stuck in your ways and probably won't move on.
That's all I have to say on the matter.

Thanks 

QrizB

You do sound rather evangelical about this!

Good luck with your all-electric solution. I genuinely hope it works out for you.

Newbie_John

Not sure why there is so much focus on accurate efficiency as it shouldn't matter much here. 
1kW of heat from electric items costs 24p on SVR.
1kW of heat from gas costs between 6-10p for efficiency somewhere between 50%-100%, all it matters is that it's much cheaper.

If we really want to touch efficiency then heat pumps are the way forward with up to 450%.

But they have high initial costs and any other electrical solutions requires ToU tarrif to make it "cost-efficient".

WiserMiser

One point often overlooked is that the real cost of a heat pump is extremely high. The £7500 government grant may make it seem relatively affordable (don't forget to oversize the radiators) but when it expires after 10 years or whatever you'll be hit with the full cost of renewal.

QrizB

WiserMiser said:

One point often overlooked is that the real cost of a heat pump is extremely high. The £7500 government grant may make it seem relatively affordable (don't forget to oversize the radiators) but when it expires after 10 years or whatever you'll be hit with the full cost of renewal.

Renewing a heat pump (replacing one in an existing system) shouldn't be all that much more expensive than replacing a gas boiler.

Here's a Worcester Bosch boiler  - £1412.

And an 8kW Samsung heat pump - £1910.

The difference is £500.