DamonHD

Our triple glazing ( http://www.earth.org.uk/triple-glazing-3G.html ) is a bit darker than double, but I don't think for us that it's a major issue. The make up of the triple glazed units is as follows: External pane of 4mm Clear Float/12mm Argon gas-filled cavity/4mm Planitherm Total+ Clear Toughened Safety Glass/12mm Argon gas-filled cavity/4mm Planitherm Total+ clear inner pane. Rgds Damon

Hi, Have any of you played with lamps such as: https://www.amazon.co.uk/Hama-00176548-4-5-GU10-LED-Multi-White/dp/B07FR9YBZQ/ that I could control from my off-grid Raspberry Pi vi my network/WiFi (or even the RPi’s own WiFi or Bluetooth at a pinch) without an expensive hub or complicated protocol? (In case it helps, I *do* have a recent SmartThings hub sitting unused at the moment.) My aim is to provide a ‘mood’ lamp driven by how much power we are pulling from the grid, that gets more fierce as demand gets higher especially at peak time, but that is only on when that lighting circuit is on. I'd like to try one first, and if it works probably add a second one... Note that I already have grid import/export and grid intensity available in real-time (ish) on my Raspberry Pi... Being relatively efficient (60lm+ per W, and no huge background draw) would also be good! Rgds Damon

Various of you are saying that the inverter size matters rather than panels, but I don't believe that was the case at least when I did mine. The DNO/G83 and MCS cert seemed to be all about the nominal panel capacity IIRC. Now in my case, because I was an early bird, and I think also because my array is split east-west and simply cannot all run at 100% all the time, the DNO let me put up ~5.2kWp on ~4.5kWp of inverters on my single-phase connection. Rgds Damon

Another very basic question or two since no one has recoiled in horror so far! 1) "External immersion heaters are designed to directly heat domestic hot water (DHW) in a vented system." My rad circuit is not vented so far as I understand it, but there is an expension vessel there and an emergency pressure relief value, so I am assuming that this would be OK. But please say if not. 2) "Because the Willis Immersion is such a rapid water heater, it is not recommended for use in hard water areas." Hardness is not going to be an issue as new mains water is not getting in as a source of calcium except for top-ups. But are there other corrosion or similar issues that I should think about? Rgds Damon

Background/vampire continuous load of 250W would be high IMHO. Get that down to more like 40W to cover your fridge/freezer and save > £200/y straight off! Rgds Damon

Interesting! But when we want space heat we just don't have any PV to divert! This is going to be almost entirely sucking in grid electricity. (I *will* divert any excess PV to DHW, but given mid-winter total generation is ~1.5kWh/d of which only a tiny amount is exported anyway given an a/c coupled battery...) Rgds Damon

Completely annoying that I've not been able to progress this, but it occurs to me that I might double down and be able for little extra money and effort to divert some space heat demand to electricity when intensity is low: http://www.earth.org.uk/note-on-solar-DHW-for-16WW-UniQ-and-PV-diversion.html#returnWillis Tell me why this won't work, or isn't a good idea (other than exergy)? Rgds Damon

Still using a lot of AVR (328P) and RPi (2/3/4) over this way. I'm not sure that I'd consider RS485 'old'; it continues to do a particular job, reliably. I'm hoping to buy a new piece of kit post-lockdown with an RS485 interface, for example. Rgds Damon

FWIW, I pretend that my house is on ASHP, though it is still a non-condensing gas combi, and I run the flow at about 45C. Because our insulation is (now) good, our newer rads are double-skinned but not huge, and they do fine. Look here at the new small rad tucked away behind the sofa here, replacing two long ones at either end: http://www.earth.org.uk/superinsulating-our-living-room.html#Radiators Rgds Damon

If you thought that you needed gas for cooking, from a green and a health point of view (gas cooking turns out to be horrible for indoor air quality), may I please nudge you towards induction + electric fan oven? The combo has worked nicely for us. http://www.earth.org.uk/note-on-IKEA-SMAKLIG-built-in-induction-hob.html And yes, ASHP is locking in green gains from our electricity getting greener, whereas gas locks you into burning stuff, already less green than electricity, for many many years. Rgds Damon

25W each is a bit savage. My four old-school (>10 years old) SunnyBoy string inverters (my rooftop array is in 4 parts) is drawing less than 1W per inverter at the moment. In fact 2 of yours would be about our entire overnight load (mainly the fridge/freezer): are you sure that figure is right? It might look like that with simpler (eg plain current clamp) load measuring, while actually being much lower. Rgds Damon

Sound on and good mic for the screams and buzzing please. Rgds Damon

Don't mix self-employed vs employed through own (eg Ltd) company. Quite different things from a tax and other points of view. Secondly, not all of us who used a Limited company are/were on the make. I have never taken dividends for example. And yes, I did actually consider myself on a day's notice with clients whatever the contract said. I think tha mods should remove my post and yours as political and devisive, or maybe we should avoid making sweeping generalisations? Rgds Damon

https://www.pvoutput.org/ ?

I have been 'self-isolating' for a week now, for something that seems as if it *may* be the bug, and continuing to work from home as usual, just doing without the weekly meet-up in town for an 'office day' and going to the pub. Unfortunately with the rules change tonight, my family is now joining me on lockdown for a few days at least (depending on how we do the arthmetic). Rgds Damon

Does the DNO require G98 forms to come from an MCS accredited installer? Rgds Damon

Who knows: your last thought might be a vary warm feeling inside? (I think the lasers were fairly feeble and diffuse.) Rgds Damon

MIT had a scheme with IR lasers on gimbals that could track each person and make them feel warm. David Mackay and I plotted to have IR radiant heaters come on for a short while as you entered a room, eg while rads had a chance to come up to temperature. Rgds Damon

For the record: I'm pretty sure that I've driven a 3.3V-friendly SSR, likely Crydom, directly from an AVR running at 3.3V, or an RPi, with no level shifters (I don't own any such thing!)... Rgds Damon

Very odd, and sorry about that! Try it with the www (though it works without for me): https://www.fieldlines.com/ Rgds Damon

Unless you are in a really windy location and can get a turbine ~10m above any obstructions for ~30m in all directions, then don't rely on wind alone, even with storage. A site I help look after is full of people of various levels of complete grid independence. It's hard and expensive, but can sometimes be done! Solar PV should be an important part of any off-grid system since it has several times the power density of wind, and has easier control and maintenance. https://fieldlines.com Rgds Damon

G83 and G59 were replaced by G100 and G99 on 2019-04-27. I'm not sure if the DNO will accept any of the throttling kit, as opposed to disconnecting, but I'm be pleased to be wrong. If it will then there is also stuff such as the (new) Enphase that can also auto-island and form a mini-grid balancing generation within the house, and brands such as Outback, and SMA's Sunny Island (though I have heard lots of complaints about SI). Rgds Damon

That would be comforting. Any particular downsides, eg having all the works inside including the air side, is presumably going to be quite noisy? Rgds Damon

Hi, This one? https://www.jouleuk.co.uk/knowledge-centre/?_sft_wpdmcategory=heat-pumps&_sf_s=Aero Hot Water Pump Rgds Damon

Just had an interesting chat with a chap from Ground Sun, and he'll send me over a datasheet to think about. Rgds Damon