Selling surplus off-grid via grid-tie inverter?

[SolarRoger]

Choices choices choices ...

Yes, in grid tie mode, the inverter will take care of the battery first, then sell the excess back to the grid ... Also, in this mode, your house stays connected to the grid, and you use grid/solar power as needed......if you have a very small need, the solar "may" supply all your needs during sun hours

Thanks TnAndy, that was all really helpful and is helping to shape my thoughts. There are just so many choices and it's hard deciding what is the best option from an efficiency and cost perspective, both now and for the future. I do want to have some off-grid (or backup) capability but like your idea of a separate sub-panel for 'always on' equipment and will give that some thought.

My motivation is essentially that if we decide to put in geo-thermal heating, then this obviously uses a lot of electricity over the winter. I'd like to offset that cost as much as is reasonable given that I expect electricity charges to rise over the next 10 years or more and one way of doing that is to generate as much as I can myself in the summer months and then sell that back. I'd therefore optimise my panels for maximum summer performance and not worry that much about the winter generating capacity.

My second motivation IS a degree of self-sufficiency. Mainly for things like satellite broadband and a computer plus some LED lighting and other low power devices (maybe a small fridge).

Thanks again for the comprehensive response - all excellent food for thought!

Roger

[russ]

My second motivation IS a degree of self-sufficiency. Mainly for things like satellite broadband and a computer plus some LED lighting and other low power devices (maybe a small fridge).

Roger

Self sufficiency with satellite broadband and computer?

[SolarRoger]

Self sufficiency with satellite broadband and computer?

Given what I do for a living, that's really the basics I estimate I can get my technical power requirements below 200W and given we're on top of a hill at a latitude of 43 degrees N, the figures don't look too bad ...

[Mike90250]

Given what I do for a living, that's really the basics I estimate I can get my technical power requirements below 200W and given we're on top of a hill at a latitude of 43 degrees N, the figures don't look too bad ...

I think what Russ means is, if the SHTF, who's at the other end of the sat link, that's going to pay you ?

[SolarRoger]

I think what Russ means is, if the SHTF, who's at the other end of the sat link, that's going to pay you ?

Ahhh ... OK. My definition of self-sufficiency is simply being able to run some equipment when the grid fails - which from what I can gather is a fairly regular event (I'm talking about maybe a day or two per month). So really I mean a degree of energy self-sufficency, nothing more.

[russ]

Ahhh ... OK. My definition of self-sufficiency is simply being able to run some equipment when the grid fails - which from what I can gather is a fairly regular event (I'm talking about maybe a day or two per month). So really I mean a degree of energy self-sufficency, nothing more.

Kind of hoped that was what you meant Makes good sense.

We just commissioned a generator here due to power failures being all to regular. We happen to be at the end of the line and not on a ring so if anything goes wrong we lose power - now the only problem is the cost of running the generator. As it is intended to supply 5 homes and ours is the only one occupied as of yet it is a bit over sized -