Energy efficiency

[Pfitzy]

'On average', what sort of levels are we looking at for these phantom power sucking devices? Whilst small individually, I imagine a few of them all day every day starts to add up.

Trouble with turning the foxtel box off is it takes forever to come back on line. Must try the power switch. That prob turns on quick.

We have a similar situation to iQ with the TiVo (yes, we still have one, and it still works). It takes fucking forever to switch on, and sometimes the wife's shows are on at stupid hours of the day, so I don't put a timer on it as a result. So it sits there chewing about 40-60 watts in timeshift mode according to the manual. The bastard.

Most devices like flat screen TVs, computer monitors, etc use about 1-2W in standby mode. Some more, some less - depends on the age of the technology, and more often on the quality of it. Its enough to keep the LED running, and any network interface that can be configured to WOL (Wake-On-LAN - can be switched on remotely).


My Sonos Soundbar and Sub hooked up to the main TV are interesting because they have a very high standby mode for a modern, connected appliance. The reason is they have multiple built-in amplifiers, so in standby they chew about 15 watts together. Again, it isn't much, but it does add up.

Throw in the AppleTV, Wii and one networked storage I have running on that (movie drive), and you're getting to an idea of what you need in standby.

I've set the timers to mirror roughly the time we're at home and awake (0700-2300 weekends, then 0700-0830 and 1600-2300 most weekdays - except Tuesday because I work *snigger* from home and have it on between 0900 and 1500).

So out of 168 hours in the week, we're only likely to turn that TV during 73 of those hours. Standby time for all that equipment if we didn't use timers is about 95 hours per week.

Add the other TV in the rumpus room, with an AppleTV, PS3 and another network storage (I'm a freak for backup after earlier, costly disasters*) and let's say we're talking 25 watts per hour of standby.

95 hours * 25 = 2375 Watt hours = 2.375kWh per week.

Looking at the average price for electricity before discount, NSW has a single-rate around 25 cents per kWh.

So that might be 50-60 cents per week I don't need to run. $26 a year. Timers pay for themselves in the first year, and as prices rise, I save more.

At the moment I'm importing only about 2-3kWh per day (http://unleashthepowerwall.com/statistics/) so this is significant in terms of my costs.

Most importantly the things I have around the house that are network connected have to be robust enough to recover from power outages on my timers. One of the network drives is pretty spesh for that, but the other has a weird database for all its media files that gets corrupted easily.


* Back in the day when we only had one PC, our honeymoon photos from NZ were copied onto it off the digital camera we bought beforehand. HDD died (bad controller) and cost me $600 to get them recovered. Wife very, VERY unhappy.

 

[Pfitzy]

Non-electronic ways to heat the home in winter

http://www.domain.com.au/advice/nonelectronic-ways-to-heat-the-home-ahead-of-winter-20160429-goi18n/

Most importantly: wear a frigging jumper!

I'm OK with the wife running the ducted heat if she's going to walk around in lingerie. Otherwise, rug up!

 

[terry j]

thanks pfitzy for another comprehensive post. I often wonder what percentage of computers are turned off o/night in australia, and the total power wasted from them just sitting and idling. Probably only because 'they take two minutes to start and I could not be bothered to spend twenty seconds turning them off'.

Ah, heating season has arrived. How many here use wood for heating? I'll have to organise it with my daughter, but when done there might be some here (or at least those who visit energy-efficiency) interested in the video I intend to make, for another forum.

Sure, it ain't the middle of the arctic, but it does get pretty nippy out here in bathurst, and being in an old heritage house built in the 1830s (two feet thick brick walls in places!...sadly tho that is next to zero insulative value) means none of the types of wall insulation products just listed above.

Anyway, just built an experimental fire system and it works marvelously. As it is intended to knock it down next year and apply what I have learned this year, it looks a little bit like a dogs breakfast but boy, talk about performance.

That is what the video (intended for another audience) will show. I have yet to do the actual figures, but it is not stretching it to think we will cut the wood needed by at least 70%, and getting better heating to boot.

One load (4 kg) warms the entire wing for at least ten hours, it can be started and burns the full load with no visible smoke at any time. That still blows me away. I measure the temperature of the gas in the exit flue...it hovers between 50-80 degrees.

No smoke = complete combustion.
Couple that with heat storage gives the gas flue temp of 80.

I would need a gas analyzer to work out the true number, but adding those two factors (the combustion side coupled to the heat extraction side) together and the total efficiency MUST be getting extremely high.

Compare that with normal wood heaters. ANY time you see smoke, all you are seeing is unburnt fuel completely wasted and thrown into the environment to choke others.

Compare that with normal wood heaters, you would be extremely foolish to put your hand on the flue. Not only do they send smoke (unburnt fuel) up the flue, they throw away so much of the hard won heat energy straight out of the chimney.

Anyways, as can be seen it is a very strong personal interest that may not be shared by others. And 'improvements' like these might not get the kudos or attention that the more 'high tech' and glamorous ones do. But to my mind they are every bit as real and valuable as the share market glamour boys.

 

[Pfitzy]

Awesome! Considering the number of wood heaters still in Australia - particularly rural areas - that would be great to have.

Keep me posted.

 

[Pfitzy]

Also - not sure how possible this is - but if there was a way to make a portable version i.e. camping stove, that would be a great idea.

 

[terry j]

Also - not sure how possible this is - but if there was a way to make a portable version i.e. camping stove, that would be a great idea.

yes, those are possible. There are two parts as mentioned, the combustion part and then how you 'harvest the heat' from that complete combustion. that harvesting is best done by lots of mass, which heats up slowly and then conversely slowly releases the heat back (over quite a long period of time) which is why so few burns are needed.

Anyways, that is a little background to why your portable version would work, just transport the combustion unit and not the mass (we are talking tons in a large version). The theory is actually veeeeery interesting. How it works in practice is also fascinating.

In a nutshell, much care is given to NOT taking any heat from the combustion itself. Straight away we can see it works in polar opposite fashion from the normal wood heater, where the heat ONLY comes from the fire itself. Think about it, take heat from the fire itself and you quench the fire which then can only give you incomplete combustion. Hence the smoke. So the firebox is very very heavily insulated, the ideal (which never works in the real world) is no heat taken from the fire at all.

There are a few 'tricks of the trade' to make it happen practically, but we have complete combustion. The real magic is 'how then, if we don't get heat from the fire where do we get the heat from?'

We harvest the exhaust. Wood itself does not burn. Same as petrol. You can extinguish your cigarette in liquid petrol. BUT, petrol vapour and oxygen is highly explosive. Same principle with wood, heat breaks down wood into its constituent parts which are highly flammable when combined with oxygen. A look into the back part of the combustion chamber looks exactly like a propane torch, which in essence is exactly what it is (tho not propane chemically of course), a highly combusting mixture of oxygen and wood gas. It is astonishing to look at the wood burning away gently at the front, and at the output this roaring inferno from the depths of hell.

So back to your posed idea, all that is required is a 44 gal drum (say) fitted over this outlet I have been talking about, it gets really.really.damned.hot. Instant radiation from an easily transported item. Equally it can be seen it has no heat storage as lots of mass does, but different situations have different needs and wants. In my house, I want long term heat storage, but if I go into the workshop for only a couple of hours, I'd want instant heat now and for only as long as I am there.

Horses for courses.

I have idly wondered about having, and renting, a few of these for the bathurst race weekend on the mountain. They'd love it.

Pizza ovens are all the rage now, one of these babies firing for half an hour or so up into the oven would get it piping hot in no time, all without smoke and with huge fuel (wood) savings.

There is a guy in the states who does these commercially, and he has a range of portable heaters just as you speculated. Made of aluminium (for lightness obviously) and easily assembled on site. For those of us who *know* the tech it would be easily duplicated at home.

http://walkerstoves.com/photos-and-video.html

check out his little demo on how to light them. Note (in the first vid, the short one) that as the fire starts to the left where the exhaust is the 'raging gas fire' that seemingly bears no resemblance to the few pieces of kindling causing it. It really is remarkable.

Note too how the fire burns, it burns sideways. That style is a very basic style, a lot of people use it and feed any sort of twigs, bits of wood found laying around. I am too lazy to use that style, I use a more advanced version where I load a full load into the firebox, close the door and it merrily burns away for a few hours. Of course, mine uses a lot of mass that captures damned well nearly all of the heat you can see given off by the exhaust in the video and gently radiates it back in infrared for hours.

Fascinating stuff, a real 'bloke' thing. It will always be the blokes staring absently into the fire with a beer in hand at the BBQ, the women are all off chinwagging! I think it must be something very primal deep in our DNA.

 

[Pfitzy]

I agree - nothing like sitting around the fire with the family.

I haven't really thought about the engineering implications, but what would be the effect of a double-walled drum in your 44 gal example above? A sealed layer of air in between layers of metal, to slow the radiant heat leakage and also act as a bit of a safety barrier for the heat.

Might be the difference between "fast heat" and "slow heat" if you had an internal flue that allowed the core layer to rapidly heat the external air layer as well.

 

[terry j]

I agree - nothing like sitting around the fire with the family.

I haven't really thought about the engineering implications, but what would be the effect of a double-walled drum in your 44 gal example above? A sealed layer of air in between layers of metal, to slow the radiant heat leakage and also act as a bit of a safety barrier for the heat.

Might be the difference between "fast heat" and "slow heat" if you had an internal flue that allowed the core layer to rapidly heat the external air layer as well.

Well, (if you saw) the video it is clear that the amount of heat released is very large indeed. As seen in the video (tho at the end he had a boiling pot on top) 'as far as the fire is concerned' what happens immediately after the flue exit is of no concern at all. It can either go straight into the atmosphere as in the video, or we can harvest it. Whatever heat we do not harvest is lost for good. And the fire don't give a shit either way.

So, if we slow down the absorption and re-radiation of the 44 gal drum, the excess heat simply goes out to the atmosphere. In other words, there is little to be gained by slowing down the release of heat from the drum, and in a 'BBQ setting' where this arrangement is likely to be used the maximum heat gained is desired.

Also, and I think it works this way, as air is an EXCELLENT insulator, about the best there is, it only acts as insulation if the air space/spaces are very small. Once it becomes *large enough* (as it would be in your example) and normal convective currents can form, then it becomes 'normal air' even tho trapped, and offers very little insulation.

The drum has to be 'sealed' in some way, with only the heat input from the combustion unit, and an exit flue. All draft would be lost with leaks. However, once you realise this (and that a lot of heat is still going up the chimney of the barrel-and there WILL be a lot going up, the drum simply cannot shed that amount of heat) then there is a simple and elegant solution.

The output of the first drum becomes the input to a second drum! It then operates exactly as the first drum, heats up, sheds the heat and exhausts to the atmosphere. Yep, if THAT exhaust gas is still hot enough, we can keep adding drums.

Brilliant aint it!

 

[Pfitzy]

Didn't watch the video yet. Had a visitor from Reposit Power so was busy nerding out about electricity. But what we're discussing here is equally as exciting because of the lower entry base for technology.

Just gone up to hospital to drop the wife off for surgery, so sitting in cafe with limited reception, and just another idea:

This system you're talking about needs to be hooked up to water for heat storage. Could do a whole house, very efficiently, with not much combustion.

Also off grid applications, cabins etc.

My mate is a metal worker - fucking genius one at that. Might have a word to him.

Most watch video.

 

[terry j]

Didn't watch the video yet. Had a visitor from Reposit Power so was busy nerding out about electricity. But what we're discussing here is equally as exciting because of the lower entry base for technology.

Just gone up to hospital to drop the wife off for surgery, so sitting in cafe with limited reception, and just another idea:

This system you're talking about needs to be hooked up to water for heat storage. Could do a whole house, very efficiently, with not much combustion.

Also off grid applications, cabins etc.

My mate is a metal worker - fucking genius one at that.

Most watch video.

Yes, 'low tech' but I agree with 'just as exciting'. In fact, if you think about it (and living very comfortable middle class lives in australia we tend to not think about these things) as much as your hi falutin' magnificent solar installation gives me a little stiffy, the fact that it is so expensive and hi falutin means approx 99.9% of the worlds population will never own one.

The overwhelming vast majority of the worlds population are 'down' at this basic level. In many places in africa that means almost complete deforestationfor miles around, women having to go that far to get wood for cooking. (and natch, that is a womans job no?) Then burn that wood in the hut (with a suckling child on their hip) breathing in the smoke, either from their three stone fire or the neighbours'.

It REALLY is a problem in many parts of the world. there are a lot of foundations trying to get this technology to these people.

Hooking up to heat water is doable, but the complexity rises greatly. In fact, for the last (how many?) years we used a wood boiler in the cellar, which heated water and pumped it thru radiators into the various rooms. For about six months I spent a great deal of time and effort into modifying the boiler and convert it to the rocket technology. It can be done, but after all that effort I realised it did not make a lot of sense. Too many details to go into.

(man, am I dumb) then it finally dawned on me to just build it in the kitchen. Duh. Why burn it, convert it into hot water, pump it through the house, finally get heat from the radiators. All those conversions and wasted energy. So this temp test heater was installed, and boy it exceeds anything I hoped of.

Metal in these stoves. Basically, there is a saying in rocket circles...'Metal is doomed.' Usually that is all in capital letters. Even SS corrodes, and they go pretty quickly. It is all refractory material to stand the intense heat inside the working parts.

An awful lot of these are built by off gridders, for the very reasons you state. They are the guys who can heat their houses in a Montana winter using nothing but sticks etc they pick up off their property.

 

[Pfitzy]

Yes, 'low tech' but I agree with 'just as exciting'. In fact, if you think about it (and living very comfortable middle class lives in australia we tend to not think about these things) as much as your hi falutin' magnificent solar installation gives me a little stiffy, the fact that it is so expensive and hi falutin means approx 99.9% of the worlds population will never own one.

That will change - the price of solar PV continues to drop, and it is starting its journey into the third world because of battery storage. There are people in remote villages who have things to add, and via Google's Loon project, they'll get internet.

Via various projects involving batteries and storage (like this: http://e360.yale.edu/feature/african_lights_microgrids_are_bringing_power_to_rural_kenya/2924/ ) they'll get electricity. Somewhere to charge their phone and get access to all the porn knowledge they need.

I've got a post running about nuclear, which is a segue into microgrids and community independence for a future blog post about Reposit.

We're both talking about the same thing: efficiency. These people won't need to travel miles to get to what they need. An information economy can come to them.

 

[terry j]

sounds like (hope) these can all work in tandem then. The LAST thing you would use solar for is space heating.

 

[ChargerWA]

A good article on standby power. To be honest it's a little bit more than I expected. They're saying up to a quarter of all power used in the home.

http://www.nytimes.com/2016/05/08/s...version=Full&region=Marginalia&pgtype=article

 

[Pfitzy]

American figures may not necessarily apply here. They tend to be larger consumers than us on pretty much every level.

My house cycles between 120-230W overnight, consuming about 1.2 kWh between midnight and 6AM with the AV + PC gear shut off via timer. When we were in Melbourne everything except the fridge and security alarm were turned off - I'll have to get the figures from that

sounds like (hope) these can all work in tandem then. The LAST thing you would use solar for is space heating.

Agreed, but opportunities for fire-based heating are also difficult in some situations.

 

[boyo]

How to save on winter heating
http://www.smh.com.au/money/saving/how-to-save-on-winter-heating-20160526-gp4c0t.html

 

[Pfitzy]

And this time of year is probably where you get more value out of double-glazing, if you had the money to install it in the first place.

The last few mornings around here have been bloody cold as the joyful Indian summer finally moves on. It has been fucking awesome for solar generation and export, but yet again the wife's desire to bake has occurred on days where there is fuck all sun around. Something about cloudy weather and baking with her.

In any case, shortly expecting the heating to kick in and reduce the effectiveness of the Powerwall. I take solace in the fact that I'll be paying a metric fuckton less for my first bill (due in about three weeks) than I did last year, and its all green energy.

In addition, I'm thinking about moving to TOU (Time Of Use) in order to heat the house with off-peak power, and fill the battery for rainy days at the same time.

 

[Lindommer]

Did you consider rigging up a wind turbine on your roof last week, Pfitzy? There would've been plenty of power to cope with yer missus's biscuit baking sessions.

 

[boyo]

The Chimney Sheep and other cheap ways to keep your house warm this winter

http://www.domain.com.au/news/the-c...-your-house-warm-this-winter-20160714-gq4w2k/

 

[Pfitzy]

Did you consider rigging up a wind turbine on your roof last week, Pfitzy? There would've been plenty of power to cope with yer missus's biscuit baking sessions.

Damn suburban planning permissions....

 

[boyo]

I've read that small-scale (home) wind turbines are more trouble than they are worth (your average wind-speed needs to be above a certain number for them to be viable).