Radian

Are you wanting to power the ring camera as well?

The thing is, some people in this household would just slam it on whenever they liked. If the power wasn't coming from the sun they'd do it anyway. I can ask nicely to wait until there are optimum conditions ~ or hot-melt glue an ESP8266 into the machine and leave it to that. The 3V3 is already there, the pause button just needs pulling to 0V and bob's your uncle. This is on a slow control (over MQTT) when the Joule buffer is filling at a similar rate to the 1.5kW heating element that's allowed to empty it. You also have to allow for the fact that I've got a free part-reel of these WiFi chips and relish the opportunity to make my own smart appliances for nothing other than the time I enjoy spending on coding them. Anything with spare 3V3 available is fair game to me if it draws more than a few hundred watts and can be time-shifted.

I'm not talking about massive time-shifting here. Not like the stuff will be on when the house is empty! OK, here's another example you'll love: Tumble dryer. So yes you'd be right to point out the folly but you've no doubt heard the all-important fluff-effect. So let's say the line dryer has done its bit and the crispy clothes are brought back inside and placed inside the dryer - with the Sun going in and out (very much like today). A small intervention with the OEM pause button has allowed me to enable/disable the dryer as the PV picks up and excess becomes available. There's no hurry for the results and a notification for when the job is done (or not).

Doppler works best for detecting people. The classic example being that it can resolve heartbeats. Either microwave or ultrasound is suitable. Some alarm sensors combine microwave and PIR for false trigger protection. Used to be able to get very small detectors (microwave only) for putting in cars.

Because we have a very rigid routine, a boiled kettle is expected at certain times of day. So if we always leave it primed with cold water and if within, say, 15minutes of the usual cuppa demand then gate through any surplus as a priority over other loads. This would only be helpful on days with variable PV and this is where SteamyTea's predictive algorithm might come into play. The solcast api is ideal for this with 50 free requests per day. I'm also prepared to let the kettle driver notify me if boiled earlier than expected. The regular cutout and CT will see to this. To disable it we would simply leave the kettle switched off. In the absence of battery storage, the aim is to advance/retard certain loads that can be time-shifted to make hay while the sun is shining. It will only be worth the trouble if there are lots of examples like this.

I wouldn't count on it. If the gulf stream ever stops we'll all be in the same freezing boat. After all the crazy stuff that's happened over the last few years I've lost faith in the world being as predictable as it used to be. But anyway, welcome!😊

It's surprisingly flexible. And smells nice IMO ☺️ 'Tis what I'd be doing for certain.

Typical Friday job. Do they come out at weekends?

It's obviously rubbish. But don't fret, I'll give you £500 and come over to take it off your hands 🙂

@pocster has a current example of zero rate for supply and install. So if the price had been quoted to him back in March, he would expect to pay 20% less today, as indicated in the fanfare announcement by Chancellor Rishi Sunak when he spoke of "A family having a solar panel installed will see tax savings worth over £1,000 [on a typical £5000 system]" And hmrc admin are handing out advice to businesses on the hmrc.gov.uk customerforums such as this exchange: So there we are. zero rated for both the goods and the installation of the goods. Hope this clears it up 🙏

Hey pocster, tell me about the VAT you paid on the extra PV and battery here... zero rated for the materials right? But what about installation?

I'm going round in circles here. Before the spring statement I had quotes for the supply and installation of solar PV. I had a price given to me that included VAT (although I don't know how much VAT - 5% or 20% that was) At that time there were fairly arcane rules dictating how much VAT was chargeable but the companies quoting me never checked my circumstances so wouldn't have been able to arrive at the quotes without making assumptions. My assumption is that it was VAT at 20%. Now I'm getting fresh quotes after revising the spec (changed panel type to better fit space available) and I'm trying to compare the new price because it seems higher even though the company says they're slightly lower per Watt. With 20% or even 5% off I would expect a significantly lower price. VAT now should be %0 on the materials, that much is clear. However, I'm seeing mixed messages about VAT on installation labour charges. Is that also zero rated now?

I have no idea what's in paving primer. SBR is a latex solution - pure magic in mortar mixes and slurries.

Can you make a false floor using some PIR board? The trouble is, no matter how much insulation you add, after time with no air movement thermal equilibrium will set in through conduction raising the temperature in the enclosed space. If it was possible to leave an air gap between floor level and the base of the cupboard and have it open to the room with some sort of ventilation holes then that would greatly help. I'd still use some PIR between this air gap and the cupboard base.

Wow, just how long have you been living there? ☺️

I have recently had a quote that amounts to £1280 per kWp all-in, so roughly in the same ball park.

I used a roughly 50:50 mix of SBR and OPC to fix a similar issue. No need for sand. Made it runny enough to pour in through a funnel after first flushing the joint with water. Have a bucket and sponge handy if you get some on the top of the slab.

Just 31.23mm inside. You can get a pretty good estimate for the speed of light using a microwave and a bar of chocolate.

Turns out ours can too. The question now on my mind is how much more efficient it might be to combine using the microwave and resistive components. Our 900W maximum microwave power setting is actually drawing more like 1200W from the mains so is 75% efficient. Resistive heating is 100% ...but the time taken for the heat to reach the centre of food is less for microwaving so in theory it doen't need to cook for so long. I'm sure there's something to be gained from using combined heating modes but it would take a carefully devised experiment to find out by how much.

Guess who's got an addiction to class A. 🙄 The power consumption is constant regardless of volume level. Clever that.

Which other people near you paid £14 to consume. You desperately need that diverter. As you already know, once the weather shifts to anything less than predictable blue skies you run the risk of unnecessarily burning electricity. I only mention it because other people may be thinking of resorting to manual divert.

I have yet another energy saving experiment going on: Quite often the electric fan oven (Rangemaster 110) is used to cook something relatively small like three fishcakes or a few slices of garlic bread. This means 3kW is being used to heat several kg of steel and a couple of hundred grams of food. Seems wasteful. We also have a Samsung microwave with built-in grill (1.5kW) and convection oven (2.1kW max). Old habits dying hard as they do, we've never used these resistive heaters - treating it as just a microwave like the previous one it replaced. But my thinking now is that this small stainless steel box should heat up quicker than the big old range and waste less energy in the process. Anyone else make regular use of their microwave like this?

That's strange. It's such a simple bit of kit to design... So simple I recently designed my own. The problem with just using a smart switch (apart from switching a 3kW load) is ensuring that you don't import power by accident. You need to turn off quickly in response to the balance of import/export. This requires keeping track of the energy buffer (sometimes called a Joule bucket) that's part of every electricity meter.

No, because we don't take 237ml of milk with our 63ml of tea. What are you talking about? 😵

4.18 J/g°C x 1000g x 80°C means it takes 334400 Joules or 0.1kWh to boil the kettle. Probably do 5 boils between 11AM and 4PM so 15p to save. No, it makes no great sense as an isolated exercise but I'm building a list of places where I could prioritise the diversion of excess energy so I'm giving everything a chance.