Monday 27 February 2012

oh all right then

When is this party?

Ok - so it's winter and its been windy and I mustn't get carried away and staring at spreadsheets will make you go blind and all that. BUT - the purple area is the required output to meet our party date - the blue bit shows how much the turbine is over-performing. At this rate the party will be March 28 2016. But don't change yer plans just yet.... it gets less windy in summer so that blue bit should shrink. But then again the turbine was switched off for 14 hours this week.

I promise not to do another graph until the month is out!

Actually - I've just realised that I need to re-do the graph as 'actual income' vs 'projected income' cos 'income' is not a direct conversion of power output cos 'income' is higher for the first roughly 21kWh of energy generated. Oh god I guess I'd better explain this.

Based on the amassed evidence of one electricity bill, our house uses about 21kWh per day. For those first 21 kWh I've allowed an additional 'income' of 11.66p pkWh. Of course this isn't really income - it's non-expenditure - but it has the same bottom line effect as income.

If I'd paid more attention at school maths when we did this stuff - rather than daring each other to climb out of the window when teacher wasn't looking (I did very well at this - but was beaten by a pal who managed to climb out of our window and in through the window of another classroom (while a class was on in there too), steal a fire extinguisher, climb out of the window and then walk in through the door of our class and announcing to the teacher that he was checking that all classrooms had a fire extinguisher and sitting down again. Teacher looked perplexed but couldn't work out what had happened - if I'd paid more attention I'd be able to confidently express this as a formula. Instead I'll have to make it up:

income = total energy generated x FiTs + (total power generated/2) x export tariff + 21 kWh x 11.66

So there.

Anyway - revised graph may follow - only i'm losing the will to live - how about you?

Tuesday 21 February 2012

Party Invite - 28th December 2017




Sub-Title: The joy of spreadsheets
Sub-sub-title:- the irrelevance of spreadsheets
Sub-sub-sub-sub-title:- about bloody time too.

And other subsub-titles but I think you get the point.


It started almost as soon as we moved here - trying to find a wind turbine installer to survey the croft and offer us a quote. We'd succeeded in this part of the exercise in under a year - rapid progress as we now know.

Then there were long delays as we tried to get a grant from SRDP to help pay for the installation - we failed in this but things have moved on and the Feed In Tariff make the installation of renewable energy better value without public funding support.


Further delays ensued while we gnawed on our knuckles over the cost of the house renovations and the cost of getting the dairy etc prepared for the cheese making. There's been a number of big compromises here on the basis that we 'know' the wind turbine will generate income whereas the cheese enterprise is more speculative - but it's been a big sacrifice by Jussi.







And then came the delays in getting the installers and Scottish Hydro to re-quote, a delay of a couple of months to get a variation on the planning permission and generally getting the ducks quacking from the same hymn sheet.






Actual real work started around Christmas with digging trenches for the cables to run from the turbine to the byre. Then there was a pause (our main contractor's real job involves being in Nigeria most of the time so everything is stop-start :- a very typical Highland experience).

Then Jussi and the Girl went to Hamburg and things really started moving. I mention this so you feel sorry for me having to cope on my own with goats and dogs and cats and guinea pigs and chickens AND wind-turbine installers.

But 20/2/2012 is the day that the turbine was inally commissioned - and here are the piccies - including a shot of the actual generator which sits inside the nascelle - also showing the springs which pitch the turbine blades according to wind speed - very useful round here.

The total cost of the exercise, including planning permission, site surveys, the turbine, installation, groundworks and Scottish Hydro addition work is £31276:48. This is a lot. If the initial estimates of the installers are to be believed we should average a generation of 41.4 kWh per day. Based on a huge number of exceptionally wild assumptions this means that the turbine should pay for itself in 2138 days. Hence the party on the 28th December 2017. You are all invited and I promise the best home brew in the universe.


RSVP























You have no idea how much fun it is to watch the kW hours coming in - and to sit and watch the electricity meter spin backwards - as you'll see - albeit in double vision on account of the beer - when you come to the party. (You are welcome to come and visit in advance of the party of course - bookings being taken now for the summer).