#1 Nov. 17, 2015 00:10:14

From: Southend
Registered: 2012-08-01
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With these excellently detailed stats it's a pity that you don't have a Smart Meter, with their export recording capability. The financial difference made by ‘normal’ exporting beyond the deemed 50% would then be immediately apparent to most solar PV installations - the ones on the modern modest FiT rates.

Economy 10 tariff provides 6.9p/kWh off-peak import between 12am-5am, 1pm-4pm and 8pm-10pm; http://www.pvoutput.org/aggregate.jsp?id=21047&sid=18934&v=2&t=m on approx. 63% off-peak usage, 22% solar usage, and 15% peak-rate usage.
1,900kWh annually is exported, mostly in summer, on approx. 3,200kWh generation. Approx. 4,500kWh/year is imported, mostly for (a) winter and springtime off-peak Storage Heaters, and (b) off-peak hot water Immersion heating (which is “dumb”, i.e. not linked to the solar PV).
PV array is split East-West. Income is from Phase II 21p/kWh Feed-in-Tariff plus smart metered 3.2p/kWh Export Tariff.


#2 Nov. 22, 2015 16:47:22

Registered: 2012-06-14
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I record our daily PV generation stats from the inverter and input them into my own spreadsheet to monitor progress against predicted performance and to check for faults with the system. Currently the forecast in my spreadsheet is to break even in Yr 9.
System is 4Kw West facing on the rear of my house and was installed in May 2012 so my FIT payments are based on 21p per Kwh generated and 3p for export (no export meter so assumed 50%). Generation for 2013 was 4890 Kwh and for 2014 was 4926 Kwh. Cost of installation was £7875.
We monitor our Generation and Export in real time using the Owl PV Intuition system via an app on our phones and then switch washing machine, dishwasher or tumble dryer on (one at a time) whenever the surplus being exported is sufficient. Although I'm now retired and can do it manually, you can also monitor the system via internet and then switch on appliances via remote controlled sockets if you like. A further improvement project of mine is to switch intelligently and automatically using a Raspberry Pi to monitor the Owl outputs and then switch on the remote mains socket controlled appliances as required.
Of course, its all about using as much of the generated power as possible yourself rather than export it, currently we achieve close to 50% using the Owl to help us decide when to use appliances.
This year we had an Air Source Heat Pump (ASHP) system installed (£6800) to replace the mains gas CH and domestic HW. We get £700 a year back in RHI payments for 7 yrs and the system is currently performing to forecast with savings of 20-25% per month over Mains Gas. Of course, the ASHP can benefit from some of the Solar PV energy when its operational but my estimate is only 10% of the energy it requires comes from the PV. Break even point for the ASHP is forecast at 7 yrs and then its just the savings over Mains Gas after that.
Next purchase is a Plug in Hybrid car to replace my old diesel Audi. With mainly local journeys to do and daily top up charging assisted by the PV when the sun is out, I estimate substantial fuel savings, not to mention £0 car tax. Again, the government is paying £5000 towards purchase of the car, but this grant is being reviewed in Feb 2016.

Edited vince31 (Nov. 22, 2015 16:57:08)


#3 Dec. 7, 2015 13:22:00

Registered: 2015-12-07
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Hi everyone,

I am a third year Geography student at Manchester Metropolitan University and for my dissertation I am conducting a research project looking at the publics acceptance of Microgeneration Renewable Technologies (household scale solar panels, wind turbines ect…).

If you have any of these technologies installed at your home and would be willing to take a few minutes of your time to fill in my questionnaire by clicking the following link, it would be much appreciated.


If you have any queries about any of the questions or think you could help my research further by arranging an interview could you please email me at joseph.p.donoghue@stu.mmu.ac.uk .

Thanks in advance and I look forward to hearing from you.

Joseph Donoghue


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