Tuesday, November 30, 2010

Anneberg, an inspiring example

29 Nov '10: Sami (of Finland) just pointed me in the direction of Anneberg, a district near Stockholm which is an inspiring examples of interseasonal storage - better than I have yet seen (even more than Drake's Landing), and a huge vindication of what I have been doing here as a solitary adventurer, much maligned by some who don't believe it is possible. Chris Wood (who mentioned it to me a few weeks ago, but I didn't hunt down the details) points out that it has been going now for eight years.

This scheme uses interseasonal storage despite the much higher latitude - colder winters and lower sun angles in summer. There is a deeper technical discussion on this site, in english with some good diagrams:

  Quite remarkably, they are trying to do this without heatpumps, I guess trying to store enough energy to support their underfloor heating, and using electricity as a backup. The house designs are hugely dominated by the absolute imperative to face south and maximise the solar panel area.
  One of the most interesting diagrams I have seen is their attempt to guess at the losses underground and to provide enough solar thermal input to overcome this heat loss. This could be because their panel area is far larger per house than mine, and their expected ground temperature far hotter - the delta-T between their hot zone and the surrounding infinite ground will be far higher and encourage much faster leaking.
   As with mine, this cannot be measured, it can only be guessed at. My panels produce so little by comparison, that last summer, the maximum deep ground temperature reached was 14º, not significant enough for a large loss. I look forward to seeing next summer how high this goes, and will try to evolve a similar diagram with some estimate of loss. The earth should reach higher than that, as the mirrors will enhance the sunbox performance and the earth will be making a better standing start, assuming that the ground temp in March is higher than it was in 2010. Presently, it is more than 3 degrees better than in 2009.

  I have since learnt that Anneberg did not work well initially, mostly to do with technical problems from leakages, and the consequent reliance on direct electric heating. The decision to try to heat the ground to the temperature of a hot water tank so that there would be no need for heat pumps is bound to have problems, transmitting high temperature fluid a long way from each house to a distant store, and back again, and then doing the same with the fluid that is actually heating the house. It also accepts a far higher rate of loss to surrounding soil than I would be prepared to accept. 
   My sunbox system here is heating only the soil immediately below the house using existing pipe runs, and never higher than 25º even in summer. Re: using houses without heatpumps, I believe that it would be very difficult to market a house that had no heating system - its better to put something in that doesn't have to be used too often if the house performs well, but is there if it doesn't.
   However, I have also heard that the Anneberg system is working for some years now, since solving these teething problems. I have had enough problems too and it is all part of the evolution of a technology.

Sunday, November 28, 2010

Is this a perpetual motion machine?

28 Nov '10: I am having to take a helluva lot of criticism from people on the Navi tron forum, and I really dont understand why people do not let my experiment continue, and patiently wait for the result like I am having to do.
  This system has had only 2 months of the winter so far, starting from October 1. It is too early to be crushing the author with excoriating criticisms, everybody has come in for it, myself, family, children, students, job, Phd student, Datataker, Sontex... nobody has been spared.
  Come on, give me some time to test this, and to improve my expertise! This is a piece of Plumbing for crying out loud! Ground charging schemes need 5 years to get up to speed (see other articles), and some artificially boost the ground in the first few years until the sun has provided enough to reach steady state.
   I am not trying to sell them something, or compete with the company who hosts the forum, I am an individual, and a prospective customer for future projects. I am not submitting it for 'peer review', I am reporting on my findings. If a product comes out of it, NT might be the right company to take it on. So be patient!
   It is my research fund that has been expended on it, not theirs, nobody is buying anything, so what is the aggression for? I have been accused of 'not presenting it clearly' - well I am not doing a 3 minute pitch on the Apprentice, I am not selling anything, I am testing and discovering something. The blog is a 'diary' format, and key points worth presenting are stored in the Tabs at the top of the blog. There seems to be real resentment that I report on it using a blogsite, but this comes from the old fashioned pre-blog days when one might have used the forum to report every twist and turn.

   Things have been quiet recently, and I have enjoyed discussions in some areas, such as high rise, passivhaus etc. Suddenly last weekend there was an eruption of real nastiness. There is a particularly critical individual called Chris who writes:

'What David claims to have managed is another perpetual energy machine. He's in some pretty good company http://www.lhup.edu/~dsimanek/museum/people/people.htm, but at the end of the day he claims to be warming himself at the expense of , well what...? Could it be the warmth of his wall? could it be temperature of the soil in the garden? I don't know, but certainly any attempt to refine the question is being met with increasingly aggressive responses. Sadly this is another characteristic of the Perpetual energy community. The reference to their own integrity over provable data and the anger are recognised characteristics http://www.ka9q.net/crackpots/index.html.'

'And there in lies the community skepticism. Because I don't believe this is a malicious hoax, I believe it's simply an individual outside of his own area of expertise, worried because he has started to realize some of the flaws. Having re-read the 'mirrors' thread in light of the beast it has become, I'm surprised by how much consideration was given. The original premise of mirrors seems to have moved from the top to the bottom upon suggestion, and it is interesting to note both Martin and myself worried about wind blowing things off, independently, but the overriding approach has been similar to a spoilt child, I'll take my toys away if you don't play my way, wait till winter is over and how dare you question me?, cos I've got lots of massive projects waiting, and you'll lose all these orders if you don't act nice.'

  By the way, he hasn't told me anything about what he is doing other than that he has '30 tubes' - what does that mean? Evacuated tubes, doing what precisely? Heating what? I have asked more than once, and still he doesn't reveal.
  His posting isn't the only one.  He claims that he speaks for the entire 'skeptical community'. So hostile is the attitude, that I have taken to referring to my system as the 'chocolate teapot' with the 'diddly-squat mirrors' as a form of humorously self-deprecating self defence because they were calling it that enough times.
  He says he doesn't believe this is a 'malicious hoax'. We all know this is double speak of the sort "I don't believe you are a wife beater but...." that plants the idea in the mind of the reader, and followed up by his link to http://www.ka9q.net/crackpots/index.html., there is no further doubt as to the degree of malice intended.
   As for worries about my mirrors 'blowing off', I don't think he has examined my solid aluminium brackets. His reference to 'martin' was an item suggesting that the mirrors would scare passing jet planes - which I took as good humour. Martin is a gruff knowledgable person with a sense of humour.
  As for the reference to 'large projects'.... well I am doing some. As to asking whether I am heating the house from the soil in the garden, the answer is YES YES YES! Am I recycling heat from the wall back into the house, NO NO NO!
   He claims to be a moderator, but how can a moderator on a forum of a company retailing ground source heat pumps not know that heat can be lifted from the ground?
  Anybody who has seen a Stirling Engine on YouTube powered just by a cone of metal reflectors facing the sun will see what appears to someone like Chris to be a perpetual motion machine - mirror reflectors driving an engine?? Well, the news is that it stops when the source of power stops, after sunset.
  What is wrong with waiting till Winter is over? This isn't a time based computer simulation which can be speeded up, it's in the real world with a real family in a real house, and Time is the only way to test it. Other projects I have looked at, eg Anneberg, Sweden require 5 years to settle in, and Xolar in Austria require 7.
   I won't know fully how the GSHP has performed in its first real winter (using charged ground) until May 2011, and I won't know if the mirrors have changed things until a summer has completed by Oct 2011.

My reply on the forum, here's much of it:

'There are some who will continue to think that ground source heat pumps are perpetual energy machines, and funnily, I agree with you completely. I still meet people who assure me that there is no need to recharge the ground as there is 'infinite' heat down there, and so we can all cheerfully have heatpumps and draw heat up for ever. I contend that theres nothing infinite about the ground, because our boreholes are fixed in position, and can only reach a finite distance. Ground temperatures in Arizona cannot reach my house, neither can heat from under the Nottingham Forest ground.... therefore it is not infinite.'

'There is another more obvious perpetual energy machine available to us, it's there for another billion years or so before it burns out... called the SUN. It appears every day, even during the winter, even though it is often hidden behind clouds.'

'I am surprised that there is someone left on this forum who doesnt realise that the sun is a source of energy that lasts longer than our lifetimes - but Chris, welcome.'

'We are not talking about volcanic heat, that is far deeper down. We are talking about solar gain by the earths crust. Actually, I live on the edge of the city with a large open field behind me and a north-south oriented tarmac road alongside. so, yes, we could get solar. But others live in denser areas, or east west roads, where the ground is shaded by the houses and trees, and little opportunity for summer sun to penetrate. And what happens if all the neighbours have boreholes too?'

'I very much wish I had kept metering records from the time we occupied this house. I would be more sure about whether the GSHP progressed steadily for its first three years, or if it was better in its first year, and declining each year due to borehole chilling. Having made the decision to have one, it now seems crazy not to have kept records. I think there is a mentality with GSHP owners to think "Oh, we are getting all this free heat from the ground, we can cheerfully turn up the heating or have plenty of hot baths"'. 

'Having become aware that the electricity bills were far too high, I made the decision in August 2009 to record electricity meters every day, and at the same time had the thought, that logically, the ground must get colder every year. It doesnt seem credible that my deep ground can recover fully over a short summer after a long winter of depletion.' 

'As a quick aside, the present situation is:
 External air temp -5.0º
 Sunbox air temp is 23.2º 
 Heat pump heating the house, putting glycol up to sunboxes at 3.5º at 15 l/min
 Returning from 4 sqm of sunboxes at 5.2º, going down to the ground,
 Returning from ground at 7.5º, from the twin 48m boreholes.'

'Last sunday night, after 4 hours of 'resting' the deep ground temperature in my boreholes was 11.3º How many other people with GHSP at this end of November with the coldest November weather since 1993 have boreholes in double figure temperatures? We are three weeks from the solstice, and the boxes are reducing the chilling - simply that.'

'If you can get solar heat directly pumped 48m down in pipes which already exist (their embodied energy now paid for), using low powered (30W) pump powered by PV panels, what is there not to like? It is not a perpetual motion machine because the sun is the power source and it only shines in daytime, when it is not overcast. 
But this brings in the age old principle of Storage - you store things for using later. Its as old as Genesis.'

'Last year the heating of my house required 3,000 kWh.
Last year, the PV roof generated 3,325 kWh.'

'There are many ways to measure carbon neutrality (and I reject all based on offsetting or tariff tweaking), but what is there not to like about the two figures above? 
Using the grid as a store. Above that 3,000, I need power for DHW, lighting, cooking and appliances.'

Actually, storage is older than Genesis, there are examples in early cave dwellings of food stores and water stores, long before the invention of writing. Some of the earliest evidence of human activity are pots or broken pots, which would have been used to store grain or olive oil.
   I didn't start this as an engineer knowing fully what he was doing and willing to subject it to peer-review. I set out as a householder and architect-academic with an interest in plumbing to follow a hunch that I could improve things using second hand materials : the pump, thermostat, flowmeter and black panels are donated from previous experiments by others. If it works, I shall undoubtedly tighten up the monitoring regime, although people who have seen my spreadsheet think it's already sufficiently OCD!

Feb '11 postscript: If there is anything 'malicious' here it is truly expressed in the contemptuous and moronic utterings of this Chris Wyleu characters. He then embarked on a smiting campaign against me later in February, and got me banned because I objected to being smitten so much. 

Friday, November 26, 2010

Phase Change Materials

25 Nov 2010: I am awakening my interest in Phase Change Materials.
I had a parcel given to me in the School office, but it was mis directed. When I opened it, it turned out to be a package for a Mr Ciu in the research labs (only a minor misspelling there!) and it contained some cuboids that contain phase change material that has a change at 26 degrees C.
This is very interesting! The 480 balls that I have in my loft have an unknown phase change and are also difficult to stack - they would need to be buried in a water tank.  So I still don't know what to do with them.

These cuboids have circular holes through them, so you can thread plumbing through them, and stack them tightly, avoiding the need for liquid or even for a tank! Or just allow liquid to permeate though those holes.

I shall send them to the correct recipient, but will contact the supplier.

Phase changing at 26 degs is exactly what we could use for underfloor heating using solar panels! 26º is low enough to be right for solar panels to stack heat into them, and yet high enough to operate as an under floor heating source in a well insulated house (backed up by a few radiators to top up air temperature).

The other purpose of the PCM could be to be a buffer against overheating - if we used evacuated tubes in a future experimental installation, there is a danger that if the system was static for a while and then turned on, we might be getting glycol landing into the ground loop at 100 degs C - far far too hot! If the liquid runs through a Water tank, this might also get too hot. If it is run through a large crate containing PCM blocks, it would cool the liquid to a safe level but not lose any of the heat, it would simply delay it until later when the sun was not shining.

Passivhaus Highrise in Linz

25 Nov '10: The Power Tower: This remarkable 19 storey tower in Linz, Austria is the highest building that could be considered near to Passivhaus standard, requiring no fossil fuel burning for its energy requirements. It's designed by Kaufman and Haas.

As the PDF above says: "The new group headquarters of the Upper Austrian power utility, Energie AG Oberösterreich, is currently under construction in Linz. Known as the Power Tower, this is no ordinary office complex – even before completion, it is setting the benchmark for energy efficiency in large buildings. With its nineteen storeys, this will be the first high-rise office building in the world that uses renewable energies to meet almost its entire energy requirement for heating, cooling and fresh air."
   The tower has 46 x 150m deep boreholes for ground source heat pumps, plus it has 90x10m deep concrete piles with thermal loops. 6,900 metres in all! An inexhaustible source of energy!
   There is an immense amount of PV in the facade (700 sqm for 42,000 kWh/year). They are not using solar thermal  panels to recharge the ground with heat. They are doing some summer cooling of the office areas with water brought up from aquifer. Tall buildings generally have high internal heat gains, and these are even greater with highly insulated walls - so there is plenty of heat being put down in the summer - in a sense, the whole building is a solar thermal collector!
Media press release 2008 

Wednesday, November 24, 2010

Examples of Earth Charging

24 Nov'10: Here are two notable examples,
IKEA store in Tempere, Finland, the 37,500 sqm store will be heated from the ground, 60 200m deep boreholes, to be used for cooling the building in summer, and for drawing heat in winter. The article focuses on the technology of drilling through such deep rock, so I am not sure if they also use solar panels in summer. But commercial buildings produce a lot of internal heat from lighting and other internal gains, so if this is stored underground it's better than just blowing it into the atmosphere.

Xolar's roof
(image from their PDF document)
Xolar Group, Eberstalzell in Upper Austria, are a company making solar hot water systems so they are obliged to get it right in their new headquarters. It's a 21,900 sqm building that will eventually be totally passively heated and cooled. They have a huge number of solar thermal panels on the roof to provide thermal energy. The building is nearly airtight, so heat recovery is possible.
The perimeter of the building below ground is deep insulating walls, and they are charging the ground below with heat. The solar panels are charging the ground and the target temperature is 22º. For the first seven years, they are using 3 biomass (wood pellet) boilers to maintain the rate of charging through the winter. After 7 yrs, the ground should be at a steady state, where regular solar input can keep the ground topped up, so the biomass boilers can be disconnected and sold.
They are aiming ultimately to run the building at 10 kWh/m2/annum, less than the Passivhaus standard of 15. There is a very large buffer tank of water at the heart of this, and the thermostats decide whether to use biomass or solar heat, depending on the season.
The article says that in Upper Austria, 32 percent of gross energy consumption is provided by renewable energy sources, biomass being 13% (I guess a large part is hydroelectric).
See also, PDF document.
PS thanks to a friend on the Navitron forum for alerting me to these.

Monday, November 22, 2010

Ground Temperature is holding up!

22 Nov'10: A year ago today, the deep ground temperature was 8.10º. Tonight, while taking the usual Sunday night readings for the spreadsheet, and letting the GSHP pump glycol round for 20 mins, the deep temperature was 11.3º. I want it to be high, but this is far higher than I expected because the last week has been dire.... a small amount of sunshine last monday, followed by days of low fog and cloud with periods of drizzle.
   Perhaps this interseasonal charging lark is working!

   Because we seem to get quite a lot of sunny days in Feb and March, I am hoping that the usual springtime drop of ground temperature will not occur because the sun will come in early enough to prevent frosting. The lowest was in 10 January, 4.70º, with an average daily GSHP power consumption of nearly 30 kWh/day. Even if there are sunny days, we don't get much of them, due to Sharphill looming high to the South East of the house.

24 Nov: Higher consumption?
 My all time annual low of 3,996 kWh for the GSHP and 6,075 kWh for the house was achieved on 1st October'10, and since them the weekly-corrected figures for annual consumption have gone up, not down.  
   Some things are causing our consumption to be higher than last year... the calculation of the annual consumption is re-computed every Sunday. As each week is being added at the head, a week at the tail is snipped off, and I am snipping off a very warm autumn of 2009 and replacing it with a week of very cold autumn.

  We had an unusually cold Spring in 2010, and now, we are having a far colder autumn in 2010, with a cold snap in October and evening temperatures in single figures for most of November. It is still November, and a heavy fall of snow is predicted for the last week of this month.
  Another reason is that I have a deal with my wife (who is disabled and unable to exercise) to raise the thermostat to 22º whereas it was 21º last year. I am also allowing the room thermostat to have 'more influence' in the thermal algorithm of the GSHP (compared with the liquid temperature). One degree difference can greatly add to the annual heating load, perhaps another 180 degree-days.
  I will reduce the activity of the Sunboxes on non sunny days by raising the Triggering Delta-T to 6º C, instead of the previous 5º. This is from observation, that when temperatures are lower, the earning from the Sunbox is reduced, and a fast pump flow does not pick so much heat up. So one can reduce excessive pump hours by making it activate when there is a greater delta-T - either when the GSHPs' ground loop is much colder, or when there is a winter sun.

Sunday, November 21, 2010

Jussi Mirrors in Finland

21 Nov 2010: Sami from the N-tron forum pointed out to me that he knows of an installation in Finland by someone called Jussi, (Mr Juha Kirjonen) which uses mirrors.
  Finns have a short summer season with very long hours of daylight at a low sun angle so they need to try every possible trick that will help. These are self-built panels, and seem to use central heating radiators as collectors. I hear from Sami that winter temps are so cold up there that you have a risk with above ground liquid circuits, even with anti-freeze. As the winter photo here shows, there probably too much snow for them to work even if you did have plenty of anti freeze in them!
   Aurinkovoimaa is Finnish for Solar Panel. Well done to Jussi for believing in the power of the mirror! His other albums have pictures of boat restoration projects, car and heat pump reconstruction, and more. He seems to have a very large workshop.
    His Picasaweb album has pictures of the whole thing being built in the workshop - the link is:

Feed in Tariff finally paid!

20 Nov'10: I was glad to see that suddenly our bank account looked larger than usual, and I found it had just benefitted from £1015 of Feed in Tariff - Good Energy's payment from 1 April to 1 October. Actually, I shall have to complain (I don't want to sound ungrateful), but it is less than the hoped for 41.3p/kWh.

The amount over the winter will be less than one third of that, as October has been poor, and who knows what March will bring. During the winter months, the Sun is hiding behind Sharp Hill and shortening our solar hours by as much as 2 hours a day :(

Friday, November 19, 2010

Tea with Ken Clarke

Ken shares tea with Jenny
19th Nov '10: As part of NEA's Warm Homes Week, various MPs have been visiting projects in part of the country so see examples of energy saving or generating. The Rushcliffe Solar team were honoured to be chosen as NEA's example for Rushcliffe, and nominated one house for a visit from the MP for Rushcliffe, Rt Hon Kenneth Clarke. We visited the house of Jenny Johnston.

  As he is currently Justice Secretary, Energy policy is not top of his priority list, but he showed supportive interest in what we had been doing, and it was good of him to take part in the national week of action.
  As it was a Friday at the end of a very busy week, it was very relaxing for him to end the week with a nice cup of tea, non political chat, and only a walk away from his own home.

Thursday, November 18, 2010

360 degree sunbox for Finland

17 Nov '10: I have had an interesting conversation on Navitron Forum with Sami, who lives in central Finland, and has a problem with very deeply chilled deep borehole - 210 metres deep serving his ground source heat pump. It is getting well below freezing every winter. His part of the world has no sunshine at all from November to February, but during the summer he has virtually 24 hour sunshine - with very low Solar Altitude angles coming from a 270 degree sweeping Azimuth this is a real challenge.
   With such a short summer and such shallow angles, how can solar heat get deep down when the ground a metre below the surface has been frozen for months? - and most of that solar heat is used in overcoming the thermal load of thawing that frost.
  There is this very short summer season, so there is a short time to pack a lot of heat down below, so a highly efficient device is needed that can work from 2am to 10pm!

  This design idea is scalable - for a small installation it could be say, 1 metre high, but it could equally be twice as big or more in every direction (i.e. eight times bigger). The central element would have to be black and cylindrical cluster of pipes carrying glycol, and the shape of the square box would be rotated at 45º to north, so that the NE and NW faces get direct sunshine. Every face is surrounded by large bright mirror finish metal, so that there is maximum harvesting of the sunshine, even at very low angles.
  In this model, the central black cylinder could be larger. The whole thing is scalable, and it would be great to build a prototype. As I have found, it can do no harm to defrost one's borehole, even if the direct efficiency increase can take 2-3 years to measure numerically.

Tuesday, November 16, 2010

Centre Mirrors are now installed!

16 Nov '10: I have now managed to handcraft the centre mirrors, and these are now in place. I wish I had thought of it when the scaffolding was up - so much upping and downing of that ladder, not good when you also have a slight pulled muscle in your back.

  With luck these will remain reasonably clean and reflective. I notice that my upper mirrors are still very clean, but the foot mirrors are coated with atmospheric dirt and a bit of bird shit after only a month. Still, as they are not so high, they are easier to clean, and could be a task for every alternate month. I was hoping that at an angle they would be more self cleaning. Perhaps they can be coated with Wax to make the dirt stick less effectively.

  Now that the centre-mirrors are fitting snugly, I may go on further and cover the upper pipes with aluminium box enclosure.
   Also, I have yet to fit the outer corner mirrors. They are made, but still on the ground as I have to build the special hinges for them. The best angle will be 45º in summer or winter, so they do not need to swivel once established. They will stay clean for longer.
  The centre-mirror assembly you see here is of pop-riveted plates, and is not screwed in as there is a good gripping base detail with a strong Push-Fit detail at the top.

Energie - house heating from Sun, Wind and Rain!

16 Nov '10: I have just been directed to a very interesting product that is very similar in some ways to the Surya Sunbox principle. This is the Energie system from an underfloor heating company called Thermal Reflections. The system uses efficient unenclosed aluminium black collectors, open to the air, which in enough number can be the sole source of heat for a ground source heat pump. Because they are the sole source, they have to be open to the wind and rain, and the heat pump sets the appropriate delta-T to manage the heat collection, even in the dark. They can be roof or wall mounted, like mine as they need most of their heat in winter.
  My criticism would be that they would be very very effective in summer, but have nowhere to put the surplus heat, whereas my humble sunboxes quietly pump solar heat all summer long at 5 litres/min into a fifteen storey deep hole, from where I am now getting the heat for my house during the winter. Mine are an augmentation system that defrosts the ground, a similar technology but differently applied, but it is pleasing to see that the general idea, including the plumbing is very close.
  I take heart from this, and hope to get one of those panels sometime, to test. Apparently, the panel manufacturer is in Portugal. One of those panels, enclosed in a transparent case, might be more effective than our polypropylene collectors.
  The detailed document about them is:
Below this item, Chris Wood has posted a clarification of how these work: apparently they are in effect part of the heat pump because refrigerant goes to the panels.

Mirrors are working well

14 Nov '10: Well we have had a few sunny days recently, and we continue to get great performance from the boxes when the sun shines - really, some of these scores (between 17 and 20kWh) are amazing for days that are less than 6 hrs of sunshine (if it shines). The Mirrors plainly are working well, even if it's difficult to quantify how well.  It helps that the sun is so low that it is shining directly at the sunboxes.
   I have now made the mirrors for the vertical sections and will be fitting them this week. I guess that if I have the courage to get that high up the ladder, I might adjust the top mirrors for next summer so that they actually have variable tilt angle.... well they will work at 60 degrees angle in the morning and afternoon, even if not at midday.
 The real test is of the performance of the GSHP. This is still difficult to tell as the months of October and November have so far been colder than last year. You can see historic weather data on this website:
   The other test is that of the deep ground temperature - this is more convincing. I did a test of the ground on Sunday night, 14 Nov, and the deep ground was 11.4º. Exactly one year ago, with a milder autumn (and no solar recharging), the ground temperature was 8.4º. This is a massive difference for that mass of soil, and I hope it will bear fruit in the difficult months of January and February.

Monday, November 15, 2010

Rushcliffe Awards Scheme

11th Nov '10: Members of Transition West Bridgford attended the evening Rushcliffe community awards ceremony at Beckett School. We had a little bit of hope as we had some nominations - for example, for services to local business, or to the environment. But with so many things going on, and so many worthy volunteers deserving the prizes, we will have to wait another year.
   Well done to Kinoulton for their Mayor's special award, for a Greening Campaign that managed to get 50% of the village involved, which is, apparently, a national record!
Pictured are: Tina Holt (WB Ecohouses), Karina Wells (Transition WB and other things), David Nicholson-Cole (Rushcliffe Solar), Mrs Marie Males (Mayor of Rushcliffe), Sheila Hood (Sustainability officer for Rushcliffe BC)

Tuesday, November 9, 2010

Rushcliffe Solar nominated

8 Nov '10: The staff of Rushcliffe Solar are attending an awards evening at Beckett School on 11th November. We have been nominated for an award for service to the community (in the field of Energy). That doesn't mean we have won it, it's a nomination.... so let's not write more about it now, but if we do win an award, you will hear more about it here!

What it takes for Sunboxes not to work

Monday 8 Nov '10: For the first time this year, the combination of weather was such that the Sunboxes did not operate at all. Am I unhappy? No! This is how it should be!
   It was a day of heavy cloud and continuous rain, temperature level at about 4-5º all day, and only 0.40 kWh of PV in the whole day - the worst of the half year so far. There is enough heat accumulated deep in the ground that the GSHP never lowered the outgoing temperature of its ground loop enough to have a delta T that would activate the sunboxes - this would have to be down to zero, but the ground is still 11º.

This is actually a very good sign. I shall have to get used to more of these days - when its raining all day, and not particularly cold.

We had a rainy week last week, but a sunny weekend with 31kWh buried on Sat and Sun. I did a deep ground temperature test on Sunday night and the deep ground was 11.7º after midnight. Exactly this time last year the deep ground was 9.2º. That is a significant difference for such a large earth mass, considering also that we have already had more wintry days this autumn. Last year, the winter didn't really get going till December. The GSHP is using less energy in days of similar outdoor temperature than in the previous year. So that's good.
Tuesday Postscript: The morning was cloudy bright, with cold ambient air of about 6º and the GSHP sleeping (because its work was done). The sunboxes were at 28.5º, circulating glycol into the ground at 17.5º. Hmmm... that's good too!

Mirror progress
By the way, I've ordered more aluminium for side mirrors. No harm in giving it a try. These ones (illustrated) for the centre space between the sunboxes will divert midday sunlight sideways into the boxes instead of warming the wall between. It will also extend the life of the insulation that connects black panels 2 and 3 by providing a complete aluminium sheath over the pipe. I will probably extend it up to enclose the feed pipes that come in from above.

Sunday, November 7, 2010

East Leake Panels peeled their skin

7 Nov '10: Additional work has been done to the East Leake sunboxes, with the external parts complete, and the plastic skin removed. The Plumbing has not been done yet, so they are not working, but i did more to the electrics. Those are not completely finished yet, we have to have the plumbing done too.... (a bit of chicken and egg here..), but we will have it finished when we can.
  I have high hopes that the use of black metal collectors with fins will work better than the plastic ones on the Peveril Solar house.

Saturday, November 6, 2010

Voltage Optimisation... will it work?

Inset, picture of the meter that shows
the voltage reduced - 218-220v AC now.
5 Nov '10: I had a V-Phase voltage optimiser fitted today by a local company MCI. The idea is to reduce our power consumption, especially for motorised appliances (such as pumps).
  The voltage in our street is 248 voltsAC, and assuming that the resistance of the appliance is unchanged, that has to use more power than a similar one that runs to a voltage of 220 or 230vAC. The British Grid seems to run well, but mostly in the range of 240-255volts. Most appliances since 1990 have to be designed to run at 220volts.
   The only one that benefits from the much higher voltage is the Oven, because that would just take longer to reach working temperatures etc, so we didn't include that in the regulation. The kettle will be a bit slower.. but I can live with that.
   There seems no point in having bought A-rated appliances and then running them at 248 volts - so I am willing to do it now, and not hesitate a few years wondering whether to bother.
    More volts = more power consumption over the length of a day, a week, a month. So the reduction of 30 volts on everything including the heat pump but excluding the oven could be a ten per cent saving over a year - I am hoping for a few hundred kilowatt hours over the year! I will carry on metering, and report back!

  One thing it cannot, but doesn't need to do is interfere with the PV panel system. This installation is about limiting consumption. We rely on the Sonny Boy inverter to do its job of synchronization to the Grid correctly.
[Installation: Midland Cable Installation 0800-6129-640]
[See Dick Strawbridge talk about V-Phase]
In case any US readers are googling this, then it is also spelt Voltage Optimization.

Wednesday, November 3, 2010

Students visiting house

Lyndsey, DNC, Elnaz, Siamak
3 November'10: We had a day of visits, with three students from UoN inspecting the Heat pump and Solar panels at Peveril house, and then in the rain, we drove out to East Leake to look at the installation there.
Lyndsey is writing a BEng dissertation about the Interseasonal Charging, Elnaz is studying PV (having complete MArch in Technology), Siamak is in the engineering dept, and is considering Interseasonal Charging as a PhD topic.

Monday, November 1, 2010

More datalogger wires added

1 Nov '10: For some time now Blaise has wanted me to fit thermocouples directly to some of the innards of the heat pump, as a means of estimating its COP. We had the GSHP side and front panels off on Sunday evening, and I have now got a thermocouple head on the pipe IN and the pipe OUT from the Condenser, both of these leading back to ports 5 and 6 on the Datalogger.
  So, we will now have temperature readings on the in port and export pipes of the Condenser.
  Other things? well I am pretty sure that some time I will take the mirrors off the West side sunbox for enough days to get reading - with three channels datalogged, input temp, and the two return temperatures.
  Ground temperature: Every Sunday, I take a reading of the deep ground. The good news.... Better ground temperature. In 2010, we had the heating season starting more than a week earlier than usual (at the Sept equinox), we had a mini winter in mid October (with below freezing night temperatures) and yet...... the ground temperature on the 1st November was last night 11.9 degrees, whereas at the same date last year in a much milder October it was 9.90 degrees.... 2 degrees is a big deal in the context of the mass of earth that the boreholes sit in, and considering the benefits that even one degree has on the COP of the GHSP. Let's continue with the experiment, and see how it works out in the colder months. There were times in January of this year when the GSHP consumption soared beyond 30kWh per day, and I am hoping this will not happen in 2011!
  Again, to remind you, the way I do this is to leave the GSHP off for a few hours, and at about 0100, I run the ground loop pump for 15-20 mins until the turbulent flow has evened out the temperature and revealed the answer. It gives time for the ring of soil around the borehole pipes to have evened out a bit.

5th November follow up: the Datalogger has had all its summer memory flushed out (stored on B's laptop) and is now catching data for the coming winter, including condenser temperatures. For the Summer, we were collecting every 15 mins so that the memory wouldnt fill up too quickly - and the main thing being recorded was the sunbox slowly charging. This wasn't good for Autumn, because sometimes the GSHP comes on, does its business and goes off in a shorter time. So for Winter, the collecting interval is every 3 mins, so we catch almost all the heating cycles of the GSHP.

See the Comments below, discussion between Chris Wood and myself as to whether the black collectors would work better with or without boxes around them.

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