0800 0794000, free from a landline. These are not 0845 numbers, so ought to be free on some mobile tarrifs – please check first though.

These came from Orance after I had some handset issues (actually no data enabled on my tarrif due to their error) so they may only be useful for tech support. Please let me know if they are helpful.

They are likely to impact everyone living in Bassingbourn, Royston, Stepple Morden, and will completely dominate the village of Litlington (the entirety of which falls within the 2km exclusion zone which would be applied if this were Scotland). This is shown on a map here.

An action group has been formed to represent local residents.

Their December 2011 news letter can be found here (pdf)

The action group is holding a public meeting at Litlington Village Hall on Thursday 17th May at 7:30pm

Local news coverage:

• Turbine planners ‘will use public feedback’ – 3 Nov 2011
• Litlington wind farm proposal attacked by villagers – 3 Nov 2011

There is scope for the pistes here to be extended, but what there is is very good for less experienced skiers. Blue runs all the way down from the summit (or reds on the other side). The main extent of the runs (between the top gondola and the summit) are covered in 2 stages of chair lifts, and adds up to maybe 25-40 min of skiing before needing to take a lift back up. The gondola ride up from the town is about 30 minutes (in 2 stages) but you can ski all the way down (at least till 29 March 2012, when there were a handful of 2-3m sections without snow)

There are 4/5 restaurant areas on the mountain, with free wifi. Most of the lifts seem very modern, and the majority are 4 or 6 seat chair lifts. These were running at maybe 15% capacity on my trip.

Bulgaria is in the EU, and euro seem to be accepted as currency with a 1:2 exchange rate for lev. A main course ranged from £3 to £12, beer and coffee £1-£3. Although Bansko doesn’t have great transport links, a minibus transfer from Sofia airport was 60 euro per person and took 2 hours which is not much worse than the alps.

For 6 days skiing, between 2 people we spent a total of about £1200 (accommodation was cheap, but you can buy an apartment for €20,000 in Bansko)

Flights          £400 (inc parking at airport)
Apartment   £120
Lift Passes   £250 (2 adults, 6 days, including insurance)
Ski hire         £150 (x2, 6 days)

The resort website has real time weather/lift info and webcams.

A nice option for late lunch after a long morning skiing is the euphoria bar which has a wide range of good food, and seemed to be our first stop after coming down the mountain each day!

The heat pump has a dedicated electric meter, and I also show the proportion of the whole electric bill which is going to the heat pump. COP is calculated using a heat meter on the output.

D Days   Electric       COP
47.2         74   (54%)  2.36
48.1         77   (48%)  2.35
53.9         130 (88%) 2.08
79.9         155 (70%) 2.06
86.2         190 (74%) 1.78

The heat pump is capable of modulating it’s output, down to about 1.9kW input. Over a week, this is 320 kWh, so even for the colder weeks here (average daily temp 6 degrees), the heat pump is running at around 50% duty cycle – or 25% of full capacity. Flow temperature is set to vary with external temperature, between 30 and 40 degrees for the period shown.

Using the android Energy Meter app to count the pulses from the 1000/kWh LED, I sampled the power profile over a couple of hours. Indoor thermostat is set to 21, but is reading 23 at the moment (maybe I confused it by taking the thermostat outside this afternoon) and flow temp demand from the controller is 39. This should mean the pump will cut out at about 43 and idle with only the circulation pump running until the flow drops down to 35.

Logging power is a little more involved than logging temperatures, but having some detailed curves might make interesting comparison against more average temperatures.

First the whole run, 4 compressor cycles, and the 3rd one probably includes a defrost cycle.

Click for a larger version

Zooming in to the cycle including defrost (where the heat pump is drawing full power – peaking at about 4kW rather than the 2kW typical running point) Also, after the defrost cycle has finished, the pump runs at a higher power level to boost the flow temperature from about 20 back up to the target 39 degrees.

Taking just the first cycle, from end to end is 30m 13s, consuming 0.456kWh, making the average draw 905 watts. The load from the circulation pump, electronics and compressor heater is 89W.

Final screenshot is a capture of the start of a compressor run, using the remote display feature of the energy meter app.

This data should help in determining the optimum control settings for my system (which is using radiators) and give me an idea if I would benefit from adding a buffer tank to the system, or increasing the pipework to 28mm from the current 22/15.

The heat pump is a Hitachi Yutaki RHUE3AVHN1 (4.9kW input, 7.5kW output, COP 4.43 at 35/7 degrees)

4.5Kw ASHP, Whole house consumption over 24 hours 31kWh.

Flow setpoint 38, Flow 40/return 31

(click for larger image)

Looks like 15 compressor starts in a 15 hour period. This is a radiator system with no buffer tank (but bypass fed to lower coil in a 150l DHW tank).

It calls several times a week, and if I call back it says there is no need to speak to them, it’s just a courtesy call. I can remove my number from their database by sending an email with some specific details, but I don’t remember inviting them to phone me every week when I entered into an insurance contract with them.

It seems that maybe when their computer is bored, it picks people at random to try and talk to. Why it calls during the day when any sensible person would be at work is beyond me.

The new system consists of:

• 7.1 kW nominal output heat pump
• Unvented solar+heap pump cylinder
• 8 radiators
• Weather Compensation controller from Hitachi

Total installed cost £8500 plus vat (minus £800 RHI payment).

After some comissioning problems (air in the pipes, blocked strainer) there were still some teething problems due to overheating.

Step 1) Put the pump into local, then test mode, Sw 1-3 on, PU displayed. Hold both push buttons for 3 sec. Pump comes on, helps to clear out airlocks.

Step 2) With pump in normal mode, check th (without a dot). This is the target set point, and was 60 degrees, same as the shur-off temperature.

I had issues with the set point commanded by the controller, and had to reduce DHW offset and compensation factor to reduce the set point on the heat pump to below 55C. Oddly, the SSUP parameter on the controller was always lower.

See sidebar link for full installation details

Air Source heat pumps extract between 2.5 and 5 units of heat whilst using one unit of electricity, but they get less efficient when it is cold, and when the output temperature is high. Typically, they generate water at 35 celcius and this is too low for radiators to be very effective. It is also not really very good for hot water.

The Daikin Altherma HT has a two stage heat pump, and runs at up to 80 celcius. A seasonally averaged COP of 3 (for an output temp of 60C) doesn’t seem too bad, but I need to compare this like for like against a cheaper, simpler low temperature system.

So far, the installer and Daikin have both failed to come up with any data. They are pretty stupid if they think this ought to be secret/proprietary because I am fairly sure even I can make a stab at estimating it with access to an installed unit.

See sidebar link for installation details of the system I finally bought

Price £700
Tax 11/11
MOT 09/11
174,000 miles, but the engine was replaced at about 130,000 miles with a brand-new one.

Gearbox, turbo, roof and various other parts have been swapped from a donor car which had done about 70k miles (and the car has done maybe 10k since then)

Bluetooth Hands free/USB MP3 playing stereo (Blaupunkt Hamburg MP57)

Exhaust is new-ish all stainless.

Paint on the boot has peeled off, been resprayed, and not stuck too well. Also some paint peeling off the driver’s door. Doors are a little rusty although this is mainly just showing as marks on the sills.

Location Cambridge/Royston. Selling since I have bought a new CRZ, and I don’t need two fun cars, plus I no longer have time to maintain the RX7.

The passenger wing mirror is a replacement (painted red). The original is available, and just needs new glass. It hit the garage door on the way to it’s last MOT.

Click on the photos to see more from an album at picassa.