SteamyTea

If you can't put a sensible unit on it, the term should not be used, ever. There has been long discussions about this.

I found moving from Hertfordshire to Cornwall improved the air quality in my home. Good only wikipedia has this to say about the fraction of air actually changed: https://en.wikipedia.org/wiki/Air_changes_per_hour I have heard this figure quoted before.

Andrew Bissell, CEO andrew.bissell@sunamp.co.uk 0795 774 8445

Have you read though this? http://www.ebuild.co.uk/topic/17614-sunamp-pv-vs-thermal-store-heat-loss-comparison/

With the trend towards radial circuits rather than ring circuit, is there any real safety advantage in using double pole switches (general question as I can't really see why we don't have double pole switching on everything).

They can isolate an appliance easily, so yes, they can reduce a fire risk if switched off at the socket. I swap between bedrooms quite a bit and I find that flicking the switch on the unused alarm clock is useful, it don't go off at 5:15AM.

Which bit of the stock market, it has many parts So what he was saying is that the replacement batteries will cost more, changes the ROI somewhat. Is that legal, I thought they were meant to trip out for grid protection. Depends on how/where it is doing it I suppose. If only people had stayed awake during mathematics and physics lessons, we would not have this sort of selling. But then Grove said "we have had enough of experts".

Not sure, they are similar, both have limitations and different prices. I don't think there is anything fundamentally wrong with the RPi, probably more down to the scripts that I write for it. I have actually gone and dug one of my old ones out (an RPi Model B) and am just downloading the latest Debian for it (on my very slow 3G, so probably be morning when I can do anything more with it.

All pretty simple really. A Raspberry Pi is a small, fully functional computer. Some people criticise it because it does not accept an analogue input, but there are enough sensors around that output a digital signal that it can read. The ftps and AWS is just remote storage, and the SSL is just a security method to stop other people reading it. Everything should really be sent securely, just think of it as a well wrapped package rather than something in a clear plastic bag. What gets hard is setting these things up reliably so that they can be left unattended and unchecked for a few months. That is generally where 'computer' based systems rather than dedicated systems fall down. Now if anyone on here knows how to write good code and set up a Raspberry Pi to run reliably for months, let us all know.

Yes, but I have not found a decent sftp site that is subscription free.

Definitely go for a GRP roof. These don't have to be totally done on site, any half decent GRP company could make you some 8 by 4 ply sheets with some GRP laminated to them. Then they would only have to seal the joints once installed. This reduces most of the risks caused by weather i.e. too hot, sunny, dark, cold, wet. As for a green roof, they don't change the thermal properties any more than a mud roof from the experiments I did a few years back. I was never happy with the explanation that the plants transpire and help regulate temperature. If you want to reduce thermal transmission, start by painting it white, or cover it in something that will stay shiny. As for decrement delay, the calculations are fairly simple: https://en.wikipedia.org/wiki/Volumetric_heat_capacity#Thermal_inertia There is no 'magic' involved, just basic thermal engineering. There is an awful lot of bollocks spoken about it though. As a general rule, the more mass of any material you have, the closer to the mean daily energy levels you can store, once you know the energy levels, you can calculate the temperature range. It is a non linear function though, which is where it gets tricky. So you only need to put in enough insulation to keep the place warm at the coldest time, and then deal with any overheating by other methods i.e. a reflective outer surface or forced cooling. And just remember that half the time the world is dark, and a good 2/3rds of the daylight time it is cloudy. of the remain 1/6th of the day, there is probably not enough temperature difference to worry about, leaving you with a few hours a year when your house may go over 26°C. A portable aircon unit may be your best option for those few times.

Latin is a dead language As dead as it can be First it killed the Romans Now it is killing me

How much would your water and waste cost. Down here in the SW it is very expensive and having noticed that the water table is about 10m down, it may be worth me getting a borehole. Thing is I would still have to pay for sewage, which is over half my "water" costs. With PV (or most RE systems), there is a lot of talk about how much energy it produces over a year. This is all well and good, but it is delivering that energy that is important. A basic 4 kWp system very really produces enough power to boil a 3 kW kettle on its own. Over a year though it could produce enough energy to boil a kettle for 1100 hours or about 3 hours a day (more than enough for even me). So it is good for offsetting, but not good for living with. This is why they are grid connected.

Paint it green then

Yes, it is NE facing window, with the one infront blocked of with part of my boat (great living alone, you can build a boat in the kitchen). It was about 8 or 9 this morning I seem to remember. My main point is that you don't really need a lot of light to do most things, just let your iris do the work.

Right. For what that farmer robbed them off for access, they could have put an airbed in a tent on the site, they would have enjoyed the view. Then, with the cash saved, bought a place in Penzance and lived there

Are we talking about the house at Marlow Lock. If I remember rightly, it was not really a floating house, more a place that had flood mitigation (I have seen the Complete Angler flooded and kayaked though the sluices a few times).

Yes, there is too much cash floating about in the UK economy. Probably not what you meant through. There is also the problem that people are not always rational actors when it comes to some purchases. I would like to get involved. Made boats and caravans/campervans in the past, not really very different are they. There was a marine project down a while back. They had some huge blocks of polystyrene left over, ideal for pontoons.

I very much like the idea of a floating house (I am building a boat at the moment, Mk2 should be sleepable). Thing is that is really just shows that building land is overvalued and water is not.

Got my light meter out, blinds closed (they are not a perfect fit), 3 LUX, LED on, 12 LUX, old CFL 7 LUX initally, 19 LUX after warm up. My point is that there is a lot of nonsense spoken about lighting, light quality and bightness levels, colour etc. Get yourself to Poundland. Edit, just opened the blinds, got a light reading of 20 LUX Edit 2, 15 minutes later the reading is 8 LUX

Same as here, chuck it overboard

I swapped out all my 8W CFL last week for 3W LEDs About the same amount of light (never did a reading but I could for a laugh). The bayonet LED bulbs came from Poundland, for a £. So I now have a 38% energy saving. Cost me £8 If I left 2 lights on 24/7, that would be about £8 for a year. So how much do these systems cost?

You can get aerogel filled glazing, but I would think it is expensive. You may be able to make your own with silica filler and some polycarbonate or toughened/laminated glass sheeting. http://www.cfsnet.co.uk/acatalog/CFS_Catalogue__Colloidal_Silica_402.html http://www.cfsnet.co.uk/acatalog/Q_CELL_Lightweight_Filler.html http://www.cfsnet.co.uk/acatalog/CFS_Catalogue__Glass_Bubbles_403.html Depending on how much light is really needed, you could replace some roof panels with solid insulation. It should be fairly easy to insulated the walls, either internally or externally, and if you can, do the floor as well. There way be a height issue though. Easy enough to fit some thermal blinds on the windows, they can help a lot, as could secondary glazing (making it triple/quadruple glazed. These could be removed in summer. May be worth looking at the heating and seeing if any secondary heating system can be fitted. There is a large choice from a child killing wood burner, though infrared, simple fan heaters, underfloor heating etc. As this is more about comfort that the cheapest running costs and technology payback, don't look at anything that seems to be "magic", it is simply thermal engineering.

Yes

As always, you need to look at the numbers involved. So you need to know, in no particular order, the min, max and 3 standard deviations (99% of the time) for your space heating load. This will help you choose a boiler of any sort. Domestic Hot Water (DHW) then complicates it if you are running it off the same system. Basically, it cannot do both at the same time, so you loose a bit of space heating while you are heating water. So you go oversize a bit to accommodate this. All that is fairly easy to establish either from first principles or from a local plumbers experience. It gets harder when trying to work out the best options for supplying the energy and power (energy and power are different things). Starting at one end you can have normal resistance heating, just an electric heater that warms the room or water. Then you could have an infra-red heater for the rooms, and resistance for the water. Resistance water heating can take two forms, stored and unstored, so a cylinder that is heated up, or an inline instantaneous water heater (like a cheap shower). Moving up a step, you can get a solid fuel boiler, that can heat water to supply the space and DHW systems. Or an oil one, or a gas one. Then you could look at Air 2 Air Heat Pumps for space heating and resistance heating for water. Or an Air 2 Water Heat Pump (ASHP) for either just space heating (works well) or for both space and DHW. The DHW side is a bit trickier as it needs to deliver at a higher temperature, so can, when it is drawing cold air from outside, have a coefficient of performance (CoP) of 1 (one), which is, in effect, just a resistance heater. ASHP also 'frost up', so need to be sized correctly (oversized) to reduce the periods that this happens. Not a big issue (though people make it one), just a feature of the technology and physics. One way around the lowing CoP is to heat and store DHW at a lower temperature, then boost it up with an inline heater. Then there is Ground Source Heat Pumps (GSHP). These work exactly the same as ASHP, but draw the heat from the ground (actually they tend to use the ground water that passes by). They generally don't suffer from frosting, though it has been known to freeze the ground in some places (when the pipework is not deep enough and sized incorrectly). Generally they are very good and reliable, but still fail to reach a high temperature for DHW, so usually have a resistance heater built in to help out (but this lowers the CoP). Finally you can have a Water Source Heat Pump if you are by a large river or lake. These are the best, but impractical for most people. Now comes the harder bit. The environmental damage that each technology causes. This is usually based around two criteria, CO2e and resource depletion/damage. So Coal has a pretty bad environmental record. It has high CO2e emissions, is limited in reserves (though they are still huge) and wrecks the mining area. Gas and oil are similar, but better, a lot better on all 3 counts. Reserves are more limited, but still huge. Large scale Hydro has low CO2e (though the constant plant growth/decay adds to the CO2e levels) but causes large amounts of damage locally and socially (a million people moved in China). Nuclear has a very low CO2e footprint, but is expensive and not very useful for variable loads (not a criticism, but a characteristic of the technology and physics) Then moving onto the more 'renewable' technologies is Wind, a good method of generating energy, but not so controllable on the power though. To be more useful on power delivery, we would need either, a lot more turbines (like millions of them) or a decent storage methods (and the best is pumped water storage, so see Hydro for issues). Wind is not without problems, it causes great social issues (though not as great as climate change and not having electricity cause). It is cheap to deploy though and can now be integrated quite well into very large national grids (once planning has been overcome). Solar is similar, and oddly, in the UK, would use less land area (but in a different way,). It has the advantage that is is quiet, can be easily scaled, and is easily moveable (it packs up into a truck). Like Wind, it is low CO2e but does rely on some mineral depletions (not a problem today, but could be in the future). Finally there is Ocean Based Generation. The best is probably tidal flow (turbines under the sea) and then tidal lagoons (hopefully one being built near Cardiff). The worse are tidal barrage as they physical change the local environment , though can help with local flood control. They are predictable though. One problem is that when integrated into a grid, is that other systems need to be turned off. This sounds like a good thing as coal fired generation could be turned off, but it is often easier to turn off Gas and Wind as they do not need long lead in times. So not the ideal silver bullet that people thing. The very worst is wave power. They just don't last very long around our coast line. They are still experimenting with them though (I like the Hayle Estuary, it has a cafe at the shallow end). So all that, may or may not, help you decide which is the 'best' system to use. If I had spare cash, I would got for an PV assisted ASHP, UFH, TS with IL RH for DHW. Just had to get all those horrible abbreviations in. But as it is I shall stick with my storage heating on E7.