Dual Fuel Boilers (Electric + NG) to solve heating and curtailment

michaels

It

GreatApe wrote: »

Showers
Hot water
Standing heat losses from the tank

Smart meter shows for the last three days

17 KWh
18 KWh
20 KWh

I'm sure there are lots of inefficiencies in gas heating systems
As a guess on a pure electric system those numbers would be closer to 5KWh/day max this time of year

Winter is closer to 100-150 KWh/day

Our lowest summer usage is just over 20kwh per day and that is with the iboost doing some of the work. How many litres of water is that heated from say 15 degrees to 40 degrees at 100% efficiency?

I get 20kwh will heat 609l of water by 28 degrees which sounds about right for 10 showers and 2 baths?

Martyn1981

Hexane wrote: »

I've seen the comments from others about long pipe runs et cetera, but gas domestic hot water heating at only around 25% efficiency seems extreme.

Looking at my gas import records, the lowest quarter is the 3rd quarter (July to Sept) as no GCH, and ranges from 19 to 24 units over the last 4 years. Using the rough rule of 1 unit = 11kWh's, then dividing by 92 days, that comes to approx 3kWh's per day.

There are two of us. We do have a gas oven, but an induction hob, and a combi boiler for DHW. No hot water tank, no diversion ...... perhaps we smell?

Edit - Perhaps I smell - best I don't insult Wifey on social media.

Coastalwatch

Martyn1981 wrote: »

Looking at my gas import records, the lowest quarter is the 3rd quarter (July to Sept) as no GCH, and ranges from 19 to 24 units over the last 4 years. Using the rough rule of 1 unit = 11kWh's, then dividing by 92 days, that comes to approx 3kWh's per day.

There are two of us. We do have a gas oven, but an induction hob, and a combi boiler for DHW. No hot water tank, no diversion ...... perhaps we smell?

Edit - Perhaps I smell - best I don't insult Wifey on social media.

I don't think we've consumed much different during the summer months to date either. From memory around 100kWh's/month! Combi boiler and gas hob only, no hot water tank until this last month which should gobble up the majority of the 100kWh's going forward. It will be interesting to see how our gas usage in the coming months compares to that of the past! Don't think we're quite ready to rely entirely on leccy but we'll see how we manage over the coming winter and take a fresh look then!


Similar to Elizabeth 1 "I take a bath once a month,whether I need it or not".

zeupater

Coastalwatch wrote: »

I don't think we've consumed much different during the summer months to date either. From memory around 100kWh's/month! Combi boiler and gas hob only, no hot water tank until this last month which should gobble up the majority of the 100kWh's going forward. It will be interesting to see how our gas usage in the coming months compares to that of the past! Don't think we're quite ready to rely entirely on leccy but we'll see how we manage over the coming winter and take a fresh look then!


Similar to Elizabeth 1 "I take a bath once a month,whether I need it or not".

Hi

No gas used here for months & don't expect to use any 'till November unless conditions are atypical ...

HTH
Z

Reed_Richards

1961Nick wrote: »

There are quite a few triple faucet monobloc mixer taps on the market. The 3rd faucet is usually for filtered drinking water, but there's no reason why it couldn't be used with an electric water heater fed from the cold.

I could not find anything disgned for a basin rather than a kitchen sink

SL006

Duel fuel boilers, propane gas and electric, have been available for many years for caravans, see the Truma website. Can’t find such a product for domestic use though. I wrote to Worcester boilers and they said they have no plans to build one, their development focus is on duel fuel in respect of NG and hydrogen.

edgex

No one is saying dont improve building energy efficient where economical to do so

But you still need to heat water and heat homes and the three solutions are

1: Natural gas boilers: What we do today. 300TWh in NG
......

Fatal assumption that this is a fixed target.

Some of the new housing, now & after 2025, is replacing older less-efficient housing.

Older housing is still being improved. Loft insulation + double-glazing + new boiler + control system can give a considerable reduction in gas usage. If you can add in floor & wall insulation, that reduces it still further.

The other issue is that the heating demand isn't tied to excess generation.

So, you need some form of storage, whether of electricity or heat.

For a houses hot water, may as well fit a thermal store, which can be fed by grid electric, or local pv, or local thermal energy. Then when there is demand for hot water, if it's not at temperature you heat it with gas/oil/electric. It wouldn't really matter which, as the increase required wouldn't be as much as if it was normal incoming temperature.