How we calculated complete annual electrical energy value for a property with no photo voltaic panels
We began by utilizing a complete annual consumption determine of three,500kWh. That is an instance determine used, primarily based on customary MCS calculations (with the shopper at house half the day) and can be the imply, non-population weighted British electrical energy consumption in keeping with UK Authorities statistics
To calculate how a lot it prices to eat 3,500kWh of electrical energy, we took the July 2024 regional common value cap figures from Ofgem, that are:
Common Unit Charge – 22.36p/kWh
Common Standing Cost – 60.12p/day
The overall value of electrical energy, for a property with no photo voltaic panels, with the above assumptions works out to be:
Price of Imported Electrical energy + Standing Cost (3,500kWh x 22.36p) + (60.12p x 365) = £1,002
How we calculated complete annual electrical energy value and financial savings for a property with a ten photo voltaic panel system, no battery storage. On Versatile Octopus for import, and Fastened Outgoing for export
We took the identical complete annual consumption determine as above, and assume the ten x 440W panels generate, yearly, 4,400kWh of electrical energy.
Based mostly on MCS standardised calculations and steerage, a property with complete annual consumption between 3,500 – 3,999 kWh, and a complete annual technology between 4,200 – 4,499kWh, with a panel solely system, self consumes 22% of the vitality generated. This works out to be: 4,400kWh x 22% = 968kWh
This implies the rest (4,400kWh – 968kWh) of three,432kWh is assumed to be exported again to the grid.
We assume the exported vitality is paid for at a fee of 15p/kWh. That is our July 2024 Fastened Outgoing Tariff export fee.
Since complete annual consumption is assumed to be 3,500kWh, of which 968kWh is consumed from electrical energy generated by the photo voltaic panels, the rest (2,532kWh) must be imported from the grid.
To calculate the entire annual electrical energy value of this property, we are going to once more use the July 2024 common Ofgem value cap figures. To recap, these are 22.36p/kWh unit fee, and a 60.10p/day standing cost, and the talked about Fastened Outgoing tariff fee of 15p/kWh.
The overall annual electrical energy value works out to be:
Price of imported electrical energy + standing cost – (Export Financial savings)
(2,532kWh x 22.36p) + (60.12p x 365) – (3,432kWh x 15p) = £271
Versus a property with no photo voltaic panel system put in, the entire financial savings are:
Complete Annual Elec invoice of property with no photo voltaic – Complete Annual Elec invoice of property with photo voltaic
£1,002 – £271 = £731 (73% saved)
How we calculated complete annual electrical energy value and financial savings for a property with a ten panel system, 5kWh battery storage. On Versatile Octopus for import, and Fastened Outgoing for export
Based mostly on MCS standardised calculations and steerage, a property with complete annual consumption between 3,500 – 3,999 kWh, and a complete annual technology between 4,200 – 4,499kWh, with a ten photo voltaic panel system AND a battery storage with 4.1 – 5.1kWh usable capability is predicted to self eat 54% of the vitality generated.
Assuming the identical complete annual technology as above, the brand new self consumed electrical energy is:
4,400kWh x 54% = 2,376kWh
Because of this the rest (2,024kWh) is exported to the grid.
Assuming the identical complete annual consumption as above, the brand new imported electrical energy is:
Complete Annual Consumption – Self Consumption: 3.500kWh – 2,349kWh = 1,124kWh
Assuming the identical unit fee, standing cost and export fee as above, the entire annual electrical energy value works out to be:
Imported electrical energy + standing cost – (Export Financial savings)
(1,124kWh x 22.36p) + (60.12p x 365) – (2,024kWh x 15p) = £167
Versus a property with no photo voltaic panel system put in, the entire financial savings listed below are:
Complete Annual Elec invoice of property with no photo voltaic – Complete Annual Elec invoice of property with photo voltaic.
£1,002 – £167 = £835 (83% saved)
How we calculated complete annual electrical energy value and financial savings for a property with a ten panel system, 5kWh battery storage. On Versatile Octopus for import, and Fastened Outgoing for export
All assumptions stay the identical as above, aside from the import fee, export fee and standing cost, because the tariff has modified right here.
We’ve got used a weighted common import fee of 18.86p/kWh, a weighted common export fee of 16.33p/kWh, and a standing cost of 58.03p/day.
The standing cost is our July 2024 fee for the Octopus Flux tariff.
The weighted import and export charges had been obtained by wanting on the common anticipated utilization patterns for purchasers on the Octopus Flux tariff. This discovered that, on common, we anticipate our clients to import 46% of their complete import on the evening fee, 46% of their complete import on the day fee and seven% of their complete import on the peak fee.
Whereas on common, of the entire exported electrical energy, our clients export 0% on the evening fee, 82% on the day fee and 18% on the greater paying peak fee.
We then took our July 2024 Octopus Flux charges (in p/kWh) that are:
Import / Export
Evening 13.42p / 4.82p
Day 22.36p / 15p
Peak 31.31p / 22.71p
And used this to calculate the weighted common import and export fee.
With all different assumptions remaining the identical, the entire annual electrical energy invoice for this property works out to be:
Price of Imported electrical energy + standing cost – (export financial savings)
(1,124kWh x 18.86p) + (58.03p x 365) – (2,024kWh x 16.33p) = £93
Versus a property with no photo voltaic panel system put in, the entire financial savings listed below are:
Complete Annual Elec invoice of property with no photo voltaic – Complete Annual Elec invoice of property with photo voltaic
£1,002 – £93 = £909 (91% saved)
