Solar IMPORT EXPORT- confused !

DATMAN_2

Bit confused.

Connected British Gas monitor last night which showed average of 300w of grid energy being used last night

Have a 4kw Solar system with a Geo Monitor. This morning (sunny) it was showing 1kw of energy being produced.

However, British Gas monitor still showed 300w of energy. This went up when microwave was on by another 1kw.

I thought the you used the elecy from the solar panels first. Shouldn't the British Gas device say “0” until (in the above example) I am using over the 1kw that was being produced by the solars as shown on the Geo Monitor?

Scratching my head at moment!

WestonDave

Basic problem is that the British Gas monitors (I have one) are "dumb" - they can't tell the difference between electricity flowing in and flowing out. If you connect it on the last cables near the meter it will therefore pick up net import/export but you won't know which (i.e generating 1kw, using 2kw will show 1kw just the same as generating 2kw and using 1kw).

My guess is you have yours set up like mine so its measuring what is feeding the consumer unit (either from panels or from grid) so you know for example that you are using 1.3kw - looking at the Geo you can tell you are generating 1kw so subtracting one from the other gets you your net import of 0.3kW.

If you want something which shows the net position there are monitors around - Wattson do one as do Owl (if you pick the right models) - they have 2 cable clips so they can sense the differences between grid import and panel generation.

Martyn1981

WestonDave wrote: »

My guess is you have yours set up like mine so its measuring what is feeding the consumer unit (either from panels or from grid) so you know for example that you are using 1.3kw - looking at the Geo you can tell you are generating 1kw so subtracting one from the other gets you your net import of 0.3kW.

Ah yes, that would work. Thanks, I was also scratching my head. I love a good puzzle, but hate it when I get stuck.

Mart.

EricMears

Martyn1981 wrote: »

Ah yes, that would work.
Mart.

It's even simpler than that.

Generation 1 kWh, usage 700W or 1300W so nett reading would have been +300W or -300W.

Since reading went up by 1kW when microwave in use the previous nett reading might really have been 300W of import and microwave used an extra 1kW . Although it might have been 300W of export and a 1600W microwave tipped from 300W export to 1300W import.

As previously advised, get a Wattson !

The_Green_Hornet

EricMears wrote: »

As previously advised, get a Wattson !

Or an Eco-eye Smart PV or an Owl Intuition-PV, which are both cheaper than the Wattson Solar Plus.

[This is a money saving web site after all.]