Just another simple way of trending energy cost/usage.  In this case budget busting blip shows the extra xmas demand due to hosting of visitors ….. should have gone skiing !


Brultech ECM 1240 web interface sample.



Google announced plainly that Google Powermeter will be cancelled in 90 days, 16th September being the termination date.

That was an unpleasant surprise.  After drawn in with all the jingly pump of helping to save the planet they have doubtless got bored and pulled the plug.

You get what you pay for !
A timely reminder that the free services offered can be pulled at any time at the discretion of the providers.

Here is link to images of the appliances in happier days of Powermeter



Here is a list of ‘frequently asked questions’ that may help interested parties in the area considering Solar PV.

Q. Am I happy would I do it again?
A. Yes/Yes

Q. Is it right for everyone ?
A. Depends on your roof location (southerly and not shaded by trees/buildings/mountains)
……. and whether you can stomach a long-term investment
ie 10 years to break even !
(not for elderlys in there twylight years, mobile youngsters or wobbly relationships !)

Q. Can you recommend your installer ?
A. Yes, heartily – Highly recommended

Q. Technical Part – What do you have ?
A. System is a 3.95 kw peak rating installed by Tom Morley, Solar Technology, Edinburgh. Yingli polycrystalline panels and an Aurora PVI 3.6 inverter

Q. Poly or Mono ?
I am poly cos’ that’s all that was available at the time.
I have no advice on this, I would probably go for the best price for decent construction quality.

Q. What the financials/numbers
A. Installed total cost was approx 14k, I was fortunate to also gain a grant (~ 10k to me).
First year return or ‘contribution’ from FITS plus export plus less import electricity
~ £ 1650
A very rough rule of thumb is 50p per kwh

Q. Scotland is cloudy and rainy these panels are silly .. surely ?
A. Well we certainly don’t need to clean the panels !
Levels of collectible solar radiation is far better further south in Cornwall or the Sahara for sure, here are my figures in kWh for the last year. (note Dec to Feb is next to nothing)
J 500, A 430, S 340, O 190, N 75, D 29, J 66, F 11, M 250, A 460, M 500, J 500 *

Q. What is the most you have generated in a day ?
A. 27 kWh, yes it was a sunny not a cloud in the sky great day
However, today was good, certainly no heat wave has been okay and I got 23 kWh
Paradoxically, these panels become less efficient in hot weather and derate due the high surface temperatures on the roof, even by 20-25% that’s why the difference between sweltering hot and bright and windy is not so large.

Q. What about Solar Thermal (hot water heating)
A. I would have liked to do this and have reserved some roof space for this system, however, this may require a lot of extra plumbing, it does not attract the same high FITs, and for now if you have mains gas it far cheaper to use your efficient combi boiler.  The case is better if you have no mains gas supply (or a hot tub!).

Q. Do you log monitor your energy usage and solar generation  ?
A. Yes, browse through the other blog posts, I log all the electricity generate, used, exported as well as gas etc

Q. Big or smaller installer ?
A. I only had small installer quote that did not employ salesman that was I guess 18 months ago.  Drive the best price and watch out for all the predictable smoke/mirrors double-glazing sales trickery.
At the end of the day the cost is due to  the parts and spending time drilling fixings onto your roof, oh and profit as well.

Q. Is it money-making or planet saving or green ?
A. Another interesting debate, but I do believe in using less and being flexible in our energy expectations. ie a longer debate for another time !

Q. Is there better ways to spend the money (on becoming energy-efficient)
Again another lengthy consideration I really can’t answer for you – Insulation, monitoring, send children to an orphanage, cruise, drink etc etc etc

I’ve been thinking about upgrading the main lounge TV for some time and currently have a 5 year old Samsung 40 inch LCD that consumes a ‘reasonable’ 230 watts. In it’s day I guess it would have been a class leader.

Anyway, I have been hankering for a bigger screen, full HD 1080 support and freeview HD.  Oh, and I have noticed LED TVs with sub-100w power ratings. I had hoped by now OLED would have matured and been commercialised, but they seem to have stalled and are taking longer to come to fruition. 3-D does not cut it for me at the moment.

So, good old Makro mail tempted me in with a 46 inch Sharp model at £760 including VAT. Way down on the price when this model was launched.  The Sharp Quattron LC46LE811E really did look rather nice in the flesh and a 5 year guarantee was a nice bonus (internet sales do not qualify!). Furthermore, this model topped the energy leaderboard at an ‘in-use’ 85 watts over at SUST-IT

So its fitted, up and running and looks glorious, so what are the energy figures according to my Kill-a-watt device.

> Shop Mode – not measured
> 112w Eco Off (too bright – horrible)
> 82w Eco Standard (looks fine to me)
> 68w Eco Advanced (a little dimmer also looks great)

So there we have it a large 46 inch telly taking a meagre sub 70 watts quite remarkable.

In just 72 days the roof mounted Solar PV system has now reached the 1 million Wh barrier (or 1000 kWh)

Not too shabby.

Okay, it’s not a race, but it is both nice to see the ‘green’ investment performing slightly above expectations and there is also that childish hypnotic ‘odometer’ rollover syndrome.

Back to the numbers.

1,000 kWh generated in 72 days in sometimes sunny Glasgow, Scotland.

That’s 3.47 kWh / kWp installed.

If it were a car it would now be considered officially ‘broken in’.

Ding ding Round 2 !

Nearly a year ago I looked at solar thermal for hot water and could not justify spending money on this technology.  So it’s time for an appeal review armed with all this recent solar knowledge and experience.

Why do I want to do this ?

  • I like the idea of saving money, CO2, reducing energy usage
  • I would really like some diversity from gas/boiler
  • Maybe even drop boiler maintenance contract (further saving)

Why not to do it ?

  • Currently our hot water usage and efficiency is surprisingly very good
  • Teenage shower madness has been solved with an aerated shower head
  • Too much effort for too little financial return
  • Gas is still very cheap per kWh, furthermore the standing charge or daily fee makes it less attractive to save on gas.

When next to consider it ?

  • When the Russians ramp up gas prices
  • When the gas distribution network gets unreliable
  • When I get a new boiler (a long time away)
  • If the RHI Renewable Heat Incentive scheme made it more financially attractive (cannot see that happening now)

Measuring Hot water gas costs
As you may know I’m now logging gas usage with the Brultech ECM 1240

What would I have proposed to fit at this point in time ?

  • Something like the Navitron high efficiency double wall evacuated solar tube panels
  • A new unvented highly insulated twin coil tank with electric backup heater.  (Maybe a thermal store – budget dependant)
  • Reconfigure boiler from direct HW to system boiler

Budget ?

Well assuming no RHI payment it would be a DIY low-budget outing ~ £1500.  Sized to provide 70% of hot water from the solar collectors.  This represents a 20 year payback for my current situation.  Note, that for ‘normal’ family using more hot water than us I reckon 10 years and for those using electric heating it would then be a no-brainer 3 years.

Appeal rejected – case dismissed

Not the best photograph, but my new toy –  an Android HTC Desire currently version 2.1 (waiting on full flash 2.2 froyo)

Anyway, nice to report that the flash lite bundle worked on the standard browser without any tweaking.  See the snap below for a Google Power Meter working nicely on wifi.

Try that on an iPod !