billt

If it's a 3 phase PV system but the house is only on one phase then you're likely to be only consuming 1/3 of the PV output.

The decent heat pumps will have the option of some sort of extra protection for salty areas, although, if your several miles from the sea it shouldn't be that much of an issue. For instance, the Grant manual says " When installing the heat pump where it may exposed to strong wind, brace it securely. • If the Aerona³ heat pump is to be installed within 1 mile of the coast, avoid siting facing the sea. • If the Aerona³ heat pump is to be installed within 2 miles of the coast, the evaporator must be sprayed with ACF50 and this must be repeated on each service, unless a factory supplied ‘Blygold’ Aerona³ heat pump has been installed." " 3.10 COASTAL INSTALLATIONS Heat pumps installed in coastal locations are prone to corrosion damage due to exposure to the sea air. Corrosion of the aluminium fins and copper tubes of the evaporator can reduce the output and limit the lifespan of the unit. To prevent this happening for all installations within 2 miles of the sea Grant recommends using an anti-corrosion treatment. Two possible options of anti-corrosion treatment are available for the Aerona³ range of heat pumps. Blygold coating All Grant Aerona³ air source heat pumps are available in a Blygold treated version. This involves a factory applied corrosion protection coating of the evaporator. This MUST be specified when ordering the unit as it is NOT available as a retro fit option for on-site application. The coating applied to the evaporator (Blygold PoluAl XT) is polyurethane impregnated with aluminium. Once applied it seals the dissimilar materials of the evaporator from the atmosphere to protect it from the marine environment. This coating is water repellent, helping to prevent dirt adhering to the evaporator fins that could reduce the heat pump output. As with any such evaporator, it must be periodically cleaned to maintain the benefits of the coating and maintain the efficient operation of the heat pump. Refer to Section 10 of these instructions for further details of the servicing requirements. ACF50 coating This is a retro fit option that is applied to the evaporator on-site. the outer casing of the heat pump will have to removed for the evaporator fins and tubes to be sprayed from both sides. Refer to the instructions supplied with the ACF50 for more detailed information on the application procedure. Originally developed for the aerospace industry, ACF50 is a hydrocarbon based anti-corrosion compound that forms a selfhealing barrier on new metal. It is an ultra-thin fluid film that dispels any moisture (including salt water) already present and provides an atmospheric barrier preventing any further moisture coming in contact with the surface in question. It continues to creep into narrow gaps, seams, etc. providing protection for 12 months and thus must be re-applied on an annual basis to maintain the level of protection. Refer to Section 10 of these instructions for further details of the servicing requirement."

I think not, more like 100W average.

Hugh Piggott is a bit of an expert in wind turbines. https://scoraigwind.co.uk/about/ He has a realistic take on them.

Council tax bands are rated on the deemed property value in April 1991. (They were supposed to be revalued avery 10 years, just as the rates were, but haven't been in 30 years - too much of a political hot potato.) To get an idea you need to find properties of a similar market value to yours and compare. Council tax valuations are full of inconsistencies. (Market value has no particular relationship with size, energy efficiency etc although the area around the property and outbuildings could affect the value.

I have the ESI thermostat on an unvented cylinder (although I did specify pockets in it) and it works fine. You can disable the anti legionella cycle, which I have done. I run it at about 47C. The cylinder is quite small and the flow rate has been adjusted so that, even with a flow temp of 70C, the return temperature doesn't get above 45C, so the boiler should still be condensing. It only takes 20 minutes to heat the cylinder form cold so it doesn't matter too much. My only issue is that the hysteresis is too small, so the boiler fires even if you've only drawn off a fairly small amount of water.

2.5mm is perfectly adequate for 5kW if the distance is reasonably short, unless it's hidden in lots of insulation.

But it will be like the old days of one coal fire in a draughty house, you roast on one side and freeze on the other. IR heaters are used in workshops because the heating is used intermittently and locally so a low capital cost heater is adequate. A heat pump system won't work efficiently in intermittent applications - although mini-splits might be OK.

You could look at TVHeadend which will run on a RPi, as long as you don't want any of the encrypted channels. I run it on a RPi 4 with a TVHat for terrestrial TV, but it can be used with satellite receivers. Pretty low power consumption although it's a bit nerdy to set up.

No you don't. .2 acres is 970 sq.m. By the time the house is built with drive etc there'll probably be less than half that, even less if you have an actual garden rather than just a lawn. Our back lawn is 700 sq.m. and I do it with a 43cm battery push mower. We had a number of ride on mowers in our last house, the best was a Stiga out front all wheel drive mower, but we had 6 acres of grass there. Normal ride on mowers have very poor maneuverability, they tend to compact the soil, they're noisy and smelly and generally to be avoided.

Doesn't sound correct to me. You only need to upgrade if more than 50% of the existing structure is being modified and there is a get out clause which says "where technically, functionally and economically feasible." External wall insulation is probably a good idea if it's practicable but I doubt that it is enforceable under building regulations.

I don't know where you get the idea that they are less efficient than gas, properly designed and installed they should be 2.5-3.5 times more efficient than gas (that is energy out over energy in). They may well be more expensive to run than gas but that depends on your utility prices and how well designed and installed the system is. Properly done and all things being equal, at the moment running costs should be broadly similar. The heat pump itself will be a bit more expensive than a simple gas boiler, depending on size and manufacturer, but the reat of the system should be similar in cost. In the overall scheme of things the equipment expense is not that significant. When it comes to installers it's a different matter. At the moment there seem to be a few people following the double glazing,FIT and RHI examples; i.e. dodgy salesmen adding on the grant to the install costs and raking in extra profits. I've been looking at heat pumps for some years and I'm now trying to get costs for replacing the gas boiler. The ball park prices I've been getting, although without a survey, seem to be about £9000 after the £5000 government grant. My calculations bring the material costs bought at retail including 20% VAT to about £7000 (including new cylinder and replacing 2 radiators). AIUI installers don't pay 20% VAT and should be getting trade discounts so their costs should be noticeably lower. If they're charging £15,000 it looks as if they're profiteering to me.

I've no idea whether the install is OK or not but it looks insanely complex. Is that 5 pumps? Heath Robinson would be proud.

Better hope we don't get to level 18 disconnection.

I don't know about remotely, but smart meters can be used with prepayment accounts so I'd guess that the supply will be disconnected if the credit runs out just like the old prepayment meters used to.

I started my system 9 years ago when the only usable option for a battery system was off grid, so that's what I have. Saving money and arbitraging grid power were not my motivations and it was very much not economically worthwhile. The irony is that if rates go up next April as they are predicted to rise it will turn out to be almost economically neutral.

Pricing that rises with consumption is probably good way to deal with the issue of the current high prices in order to not penalise the poor too much. Have subsidised low prices for the first 5kWhr,say, a day then increase the rate as usage increases and use the higher users to subsidise lower users. It may result in lower consumption overall too. Switching off power on a rolling basis has the advantage that it is actually possible and can be done in a reasonably fair way, to make sure the pain is shared out over most of the population. Time of use variable charging is not practical for most consumers at the moment.

National grid do some reasonable forecasting, which includes worst case fuel shortages, hence the possibility of short rolling power cuts, which is an entirely rational, first world, course of action. The press get hold of it and report with the strong implication that rolling power cuts will happen, to suit their need for panic causing click bait. And, of course, we have had rolling power cuts before. My batteries are 32kWh, with another 12 kWh on the way.

That's completely understandable as the vested interests that pushed smart meters made the claim that they would save energy very loudly without explaining that the meter doesn't save anything, the consumer would have to change their usage. I don't think that the messaeg has changed much.

I get 44p form my electricity bill. The off peak rate is lower, but not much use for heating. So taking 90% for boiler efficiency (my boiler runs at low temperatures so 90% is a reasonable assumption) that gives 12p per kWh, so that needs a CoP of 3.6. I'm mad so i will probably change the gas boiler for an ASHP in the not too distant future, however the large capital cost will never be recovered, so it will mainly be done because I don't like gas. At the moment the argument that ASHPs have running cost parity with gas is not credible.

Running costs very much depend on what your rates are. At the moment here peak rate electricity is 44p per kWh, gas is 11p per kWh. i can't see any practical system getting a SCOP of 4. Of course it's always possible that the government will stop subsidising gas and remove some of the loading on electricity which would change things, but I'm not holding my breath. Then there's the cost to change, which isn't trivial. I've been thinking about changing from gas to ASHP for sometime and designing a system. Although the heat pump is sort of affordable at least 4 radiators will need replacing and the plumbing will need reconfiguring. Probably replace the cylinder as well. That's likely to cost over £10,000 in materials which makes the idea nonsensical from a financial point of view. It will also entail massive disruption. As to boiler longevity, the gas boiler in our flat has a sticker with 2004 on it, so it's at least 18 years old and still working properly.

Last time I looked commercial systems were very expensive compared to PV systems. Just before the PV FIT bandwagon started I installed a large evacuated tube solar thermal system. At the time PV was very expensive and solar thermal was a fair amount cheaper per unit of energy collected. Then FITs arrrived, PV boomed and PV prices dropped through the floor, while solar thermal prices increased slightly, then most of the solar thermal suppliers disappeared as there's virtually no market any more. PV panels are fairly simple mechanically and mass produced on a large scale; from a manufacturing POV evacuated tubes are more complex, use more materials and are smaller scale. A decent solar thermal system isn't particularly simple. You need a pump controller to ensure that the pump only runs when there is energy available, so it doesn't suck the heat out of your tank and to try to ensure that it doesn't freeze and damage the system and try and protect it from boiling and dumping all the solar fluid out of the OPV. Then there's the water temperature issue. It's quite easy to get a HW cylinder up to boiling with a solar thermal system. That means that you should have a mixing valve on the HW output to remove the scalding risk. Additional work and expense. Then there's the effectiveness issue. Solar thermal works quite well in bright sun but its effectiveness drops dramatically with low illuminance levels whereas PV produces linearly so will still harvest some energy in dull weather. And of course solar thermal is a one trick pony. It will heat water and nothing else. PV will do anything that can be done with electricity, including heating water.

You need to confirm that your opentherm controller will actually talk to your opentherm boiler. Although opentherm is supposed to be a standard it seems that different manufacturers have different accents of opentherm and don't necessarily talk to each other. I have a Veissmann 100W system boiler which allegedly has opentherm but it won't talk to my Drayton Wiser which is also allegedly has opentherm. It also won't talk to an opentherm interface connected to an ESP8266 that I tried. I also installed the Viessmann external temperature sensor to try to get weather compensation working which also didn't work satisfactorily. The low end Viessmann boilers have very little adjustment of the weather compensation curve and the only available curve didn't work well with the on/off control of the Wiser system.

This tool will give you a good idea of how much you can generate. https://re.jrc.ec.europa.eu/pvg_tools/en/ Battery size is usually calculated by working out how long you want autonomy for. If you use 8kWh a day and you want 1 day autonomy you need about 8.5kWh of storage which would be about 170Ah for a 48V battery. Note that solar production is very variable and you'll get very little in the winter when you're running the ASHP most. My system has about 15000W of panels and averaged about 4kWh per day last December but 44kWh per day in May. Being further south and probably having a better site you may get less variation than that but it's still going to be large.

Yes, get one of these air fryer/mini ovens that the save energy pundits are hyping at the moment. Spend £100 to save 10p. I'm pretty sure that all ovens will use on/off switching. It's cheap, reliable and there isn't a rational case for using complex electronic control.