Renewables: "talking 'bout my generation"

John_Pierpoint

The salesman's forecast was 3070 kWh - I wonder if "Cardew" would believe it.
3748 kWh generated (the inverter tried to boast 120 kWh more - it is American)
7200 kWh of economy 7 electricity imported.
4500 kWh of day rate electricity imported.

Current costs per unit approx 12p day rate & 6p economy 7 rate (plus what is in effect a standing charge)

Ambitions to get a new log burner and a GSHP.

Household of two retired empty nesters.

It is difficult to compare current consumption with longer term average usage, because the last two years have been disrupted by illness, death then probate, clearance & sale of widowed MIL's house. Here is a guestimate:
500 - 700 kWh of economy 7 electricity (Summer time hot water from inverter plus some shoulder season heating and night to day swapping of some washing & dish washing. - eg: I have dumped 4 hours of generation into a small storage heater today)
700 - 1000 kWh of day time generation used for washing, cooking dish washing and beverages, but some of the benefit has been taken as increased "comfort" (eg turn on the electric heating in the sun lounge while watching the wild life on the lawn, because the electricity is effectively "half price").

Money saving perhaps £35 + £ 70 = £105

Payments from British Gas, which has made 4 payments, but for a year that was about 3 weeks "short":
£488.12 + £621.34 + £449.79 + £158.39 = £1717.64

Oscargrouch

Below is a typical Saturdays usage of Solar Power on the right hand side pie chart, before I had the OptiPlug



This is a Saturday usage two weeks later when using an OptiPlug.



From the above, hopefully it shows that the use of PV is greatly increased. The generation for both the days was similar, apart from using a small oil filled radiator on the more recent dated example. During the last two days of use of the OptiPlug my Energy Usage has jumped to 22.32kWh; and my EDF meter has only increased by 11 kWh.

8.3 kWh today, not too bad. C'mon Eric; 1/4 of a thanks in the book.:rotfl:

Edit: Blue on the left chart shows houshold usage.

Fairwinds

Anyone have a Aurora invertor and use the software that comes with it. I can't get it to show generation through the day, although can download a daily generation figure.

Martyn1981

11.2 today, it's going up fast already, and March target is double Feb's!

More importantly, approx 2kW from 9am onwards, so breakie, washing machine, tumble dryer, lunch (induction hob, toaster and microwave in turns) washing machine and more tumbly, import went up 1kWh from 7am to 5pm.

That'll do pig, that'll do.

Mart.

Oscargrouch

Fairwinds wrote: »

Anyone have a Aurora invertor and use the software that comes with it. I can't get it to show generation through the day, although can download a daily generation figure.

Bin it; it does not work.
Edit: Inverter is fine, works very well, get something like a Wattson Solar Plus, if you want accurate 'Anorak' figures.:)

sly_dog_jonah

13.6kWh in Cider Country, and 6.0kWh diverted to the hot water tank by the ImmerSUN.

Ignoring losses from the well-insulated tank, 6kWh is equivalent to a 24C rise in the temperature of 210litres assuming no usage during the day.

Oscargrouch

k66 wrote: »

Also if for example an appliance needs 1800 w and only 1500 w is available what happens .......... does it operate the appliance and draw 300 w from the grid or does it wait, so many ???s in my head.

Just to clear this up for you, OptiPlug does not allow you to use any free power that you have not got available. If you have calibrated an appliance at its lowest setting then once your PV system is making that in excess of what you are currently using in your house, it will switch on. If your panels then have a 'cloud burst' it will shut that applience off which is plugged into it making sure that whatever is plugged in to OptiPlug never costs you any money.:) Mind you, there is an overide switch as well, so if you are determined....... Pay the Bill..:mad:

John_Pierpoint

sly_dog_jonah wrote: »

13.6kWh in Cider Country, and 6.0kWh diverted to the hot water tank by the ImmerSUN.

Ignoring losses from the well-insulated tank, 6kWh is equivalent to a 24C rise in the temperature of 210litres assuming no usage during the day.

"z" did a masterful explanation of the amount of electricity that can be dumped into a hot water tank, some months back - I wish I had kept a copy (must go hunting for it when I get more time).

The heat losses he quoted for assumptions of the excess temperature of the tank were surprisingly high.

All I know is that I have a relatively small tank and thus tended to run it at maximum temperature (thus maximising heat loss and need to replace immersion heaters) so that it would not run out of hot water between economy 7 top ups. Unused it takes about 2 days to become too tepid for a shower.

Fairwinds wrote: »

Anyone have a Aurora inverter and use the software that comes with it. I can't get it to show generation through the day, although can download a daily generation figure.

Oscargrouch wrote: »

Bin it; it does not work.
Edit: Inverter is fine, works very well, get something like a Wattson Solar Plus, if you want accurate 'Anorak' figures.:)

In too have an Aurora, details as posted above. I also have modern flashing meters - in the final analysis it is what is on the importing and the generation meter that counts. As an Economy 7 user I have a choice of 12p or 6p electricity (those are VAT inclusive prices).

From a purely selfish point of view, if the electricity is costing less than (say) 6p a unit for an electrical home and 4p a unit for a gas home, it makes sense to use the PV generation, even if some electricity is being imported by the appliance.
(A whole new market for E-bay second hand storage heaters?).

To make sure we are all singing from the same hymn sheet, it might be useful to make sure we know the model of our Aurora inverter.
Presumably all three of us have an inverter, which scrolls through a list of about 20 parameters, one of which is the release of its software.
The failure of the software to recognise a leap year did not inspire confidence !

I have already listed typical readings from mine, this time last year - I will try and see if I can find it, or re post with the current readings.

Do you have the small fist sized desk "gizmo" - Oscargrouch has ditched his for a more impressive set of "detective" software.
Initially I tried to reprogramme mine, but realised I was making things worse. So I retreated back to the factory settings. The graph and "instantaneous" power level is reasonably accurate BUT the "day so far" figure can be wildly over estimated, especially in low generation conditions.

As posted above, even the apparent generation from initiation on the inverter is optimistic - perhaps it is recording the out put of the panels not what it manages to stuff back against the voltage of the mains.

KevinG

At last, something worth reporting! 7.53kWh yesterday, nice sunny day and best since September. 6.23kWh on Sunday. Things are looking up, although I'm not, without proper protection

sly_dog_jonah

John_Pierpoint wrote: »

"z" did a masterful explanation of the amount of electricity that can be dumped into a hot water tank, some months back - I wish I had kept a copy (must go hunting for it when I get more time).

The heat losses he quoted for assumptions of the excess temperature of the tank were surprisingly high.

All I know is that I have a relatively small tank and thus tended to run it at maximum temperature (thus maximising heat loss and need to replace immersion heaters) so that it would not run out of hot water between economy 7 top ups. Unused it takes about 2 days to become too tepid for a shower.

We are regular users of hot water (bath for baby & toddler in the evening) so the losses aren't of too much concern. Our tank is quoted as having a Standing Heat Loss of 1.85kWh/24hrs, i.e. <0.1kWh per hour.