Hello! - just starting out on a potential project

[TabWheeler]

Hi I'm thinking about building an eco off-grid home in mid-Wales. lowest possible cost and as much DIY as possible. Here to learn and beg for help!

 

Cheers

 

Tab

[JohnMo]

Welcome 

[Crofter]

Welcome aboard!

When you say off grid, do you mean no mains water/electricity/drainage/gas?

[Hastings]

Sadly, off-grid is unlikely to be as eco as being on grid due to the embodied carbon emissions of all the kit you need if building new and therefore required to meet full building regs and planning that often includes eg. strict private water supply standards). If you can have a reasonably large wind/water turbine (most of us are not allowed) then it could be different.

 

The UK grid has apparently reached the point of enough green-ness now that installing just solar panels on individual houses is borderline in terms of saving any carbon emissions, depending somewhat on which country makes the PV you buy. Info from an article on Circular Ecology (Dr Craig Jones the Life Cycle Assessment UK based specialist) I read a while back.

[Jilly]

There was someone on here who did pretty well being off grid because they were used to living on a boat and so minimising their electricity usage. 

[Crofter]

1 hour ago, Jilly said:

There was someone on here who did pretty well being off grid because they were used to living on a boat and so minimising their electricity usage. 

I can relate to that. I'm currently living on a boat, using 1150w of solar and a couple of lithium batteries. Powers all of our needs including cooking- unless we have two dull/rainy days in a row, when we have to turn the gas on.

It's possible to be very frugal with energy. Cooking is far and away our biggest power user, so when we're running short we tend to switch to pressure cooker meals or stir fries which only need a few minutes cooking. And when we have enough power, we can do a big meal (tonight was pork chops and chips, done in the air fryer).

I don't know how it stacks up in terms of carbon emissions, but based purely on price, I think we must be approaching break even- small bottles of gas, as used in boats, is not cheap. It's so nice to not have to buy the stuff any more.

[Hastings]

10 hours ago, Crofter said:

I'm currently living on a boat, using 1150w of solar and a couple of lithium batteries. Powers all of our needs including cooking- unless we have two dull/rainy days in a row, when we have to turn the gas on.

Presumably though this not all year round - you go over to mainly gas power in winter?

[Crofter]

2 minutes ago, Hastings said:

Presumably though this not all year round - you go over to mainly gas power in winter?

No, I'm on a boat, so I follow the sun.

Currently in the Caribbean...

[Hastings]

Now that's the way to go off-grid!

 

[JohnMo]

13 hours ago, Hastings said:

UK grid has apparently reached the point of enough green-ness now that installing just solar panels on individual houses is borderline in terms of saving any carbon emissions,

Been like that for years in Scotland, doesn't stop you installing PV.

 

Very little wind today, overcast, so not much wind or solar electric today. But our PV is generating enough, to cover background loads and has spiked at 1kW for short period - but saying that our grid is still zero carbon today.

 

Edited November 2, 2023 by JohnMo

[Hastings]

Lovely calm sunny day today here in the southern Hebrides and my 1.9kW PV array powered my 350W air source water heater for 6 hours, with a little spare leftover to top up the 10kWh battery bank at the same time. There was a little high thin cloud so not optimal but the array was averaging around 500W across those 6 hours.

 

150L tank of water started at 41C and finished at 55C.

[Hastings]

150L tank of water started at 41C and finished at 55C.

Incoming air temp: 12C

Outgoing air temp: 5C

 

Here's the data from my Victron EasySolar 48V 4kVA for the last 30 days:

Bear in mind that these figures are for an off-grid system in which power is only generated when there is demand. Very different numbers to a system connected to and feeding the grid (effectively 'maxed' out), which is probably 99.9% of systems posting to the pvoutput.org website (either way, you need to know which).

 

Day 7: the system shutdown due to low voltage. Caused by me being too hasty with the newly installed air source water heater.

 

Days with zero time in Absorb or Float denote that the batteries are not fully charged.

Edited November 2, 2023 by Hastings

[SteamyTea]

On 01/11/2023 at 22:03, Hastings said:

Sadly, off-grid is unlikely to be as eco as being on grid due to the embodied carbon emissions of all the kit you need if building new and therefore required to meet full building regs and planning that often includes eg. strict private water supply standards). If you can have a reasonably large wind/water turbine (most of us are not allowed) then it could be different.

 

The UK grid has apparently reached the point of enough green-ness now that installing just solar panels on individual houses is borderline in terms of saving any carbon emissions, depending somewhat on which country makes the PV you buy. Info from an article on Circular Ecology (Dr Craig Jones the Life Cycle Assessment UK based specialist) I read a while back.

You can read this.

https://www.sciencedirect.com/science/article/pii/S0378778817323101