6.57kWh/day!

Quick one.

Somewhere in March we took up the State Government's ClimartSmart Home Service and had a power meter installed. I thought it wasn't reading very accurately because the figures it was showing recently seemed quite a bit lower than the trend I'd been tracking through the regular meters.

But I hadn't read the meters for about six weeks. Did it just now - and our consumption has dropped again, down to just 6.57kWh/day for the past 44 days.

Apart from the fridge needing a bit less power thanks to cooler weather (1.2 instead of 1.5) we think the biggest drop comes from stopping our 4-yo son from having a pedestal fan blowing on his face all night, which he became accustomed to over summer. He liked it on the fastest setting.

I'll have to plug it in and measure its power draw to see if the numbers are in the right ballpark.

Stats update

It's the end of March, about to start a new calendar quarter, and a good time to review data for the quarter just ending.

Here's an interesting figure: our 1kW PV array has produced exactly half as much energy this quarter as our home has consumed. On average, the array produced 4.20kWh per day since the start of January while we consumed 8.40kWh per day. Just a coincidence - but a nice neat 50% figure nonetheless. Got me musing about the possibility of doubling the capacity and going off-grid.

On average, we exported 1.84kWh per day to the grid, which is just under half of the energy produced by the panels. Doing the sums, we must have imported just over 6kWh a day from the grid to meet our household demands.

The new fridge has been pretty steady at just under 1.5kWh per day, or 18% of our total needs. And the energy-guzzling computer my employer provided has been kept in check with an average daily consumption of 0.38kWh, or around 4% of our total. It has taken some very aggressive energy saving measures to achieve that, but I'm reasonably happy with that result.

Just one more factoid to close out the post. This week our PV array crossed the 1MWh line for total energy produced.

Quick stats

It's been a great week on the electricity front. Household consumption was 6.86kWh/day. The new fridge has averaged 1.3kWh/day, about a 35% improvement over the old one.

Excluding fixed monthly service fees but including the solar feed-in tariff, our electricity costs for the past 91 days are, in total, $2.62. That's less than three cents a day.

Stats Update

Initial figures from the meter attached to the fridge are good. Including the initial cooling effort required after turning it on for the first time, it's averaged about 1.4kWh per day over the past four days. I've reset the meter this morning to correspond with reading all the other meters so I'll be able to build up a better picture of it over time.

The other energy figures are also good. For the past 39 days:
- PV generation up to 4.62 kWh/day
- Household consumption down to 7.88 kWh/day
- Export up to 2.26 kWh/day

We've had more than enough rain recently so the tanks are still supplying water for laundry, toilet and gardening. Hot water system needed boosting one evening during the rainy period but is otherwise cracking along in the spring sunshine. Our recent rates notice showed us maintaining a significantly lower consumption than our neighbours and so I haven't bothered keeping a close eye on the water meter.

Chillin'

Remember how pleased I was when our old electric hot water system died last year? Well I have more wonderful news to share: the fridge, which at 2kWh/day accounts for almost a quarter of all energy used in our home, has also reached the end of the line. Hooray!

Its ability to actually cool things, let alone freeze them, has been deteriorating over time. I recently replaced the seal on the freezer to stop a quite noticeable cold air leak but it really made no difference. The appliance wizard (that's what he called himself) only took a couple of minutes to diagnose a failing compressor.

Decision time. Replacing the compressor would make it cold again, but cost about half of what we paid for the fridge a decade ago. It wouldn't improve the energy-efficiency of the design. It wouldn't fix the broken shelf mount or the cracked door hinge. And it wouldn't give us the extra freezer space Michelle desperately wanted. Maybe it's time for a replacement.

Had heard great things about the efficiency of chest freezers. Actually, the really interesting idea involves converting chest freezers to chest fridges. Good insulation and a lid that opens on the top instead of the side makes for minimal loss of "coolth". However, there's no way a chest fridge was going to be acceptable in our kitchen - space issues, access issues, etc - but maybe we could use a chest freezer in the laundry.

Had also seen a standalone fridge (no freezer compartment) at a school, with an energy star rating that quite impressed me. Maybe one of those for the kitchen. Time to do some research.

The most efficient chest freezers on the Aussie market, according to the official figures, are Denmark-made Vestfrost units - the same brand modified to be a fridge in the earlier link. They have one model which is about the size Michelle would like, 250L, that's rated at a quite frugal 237kWh/year. Would have been a candidate if they weren't so physically large and surprisingly expensive. And imported from the other side of the planet.

Mid-sized efficient freezer options beyond that are surprisingly limited. We quickly narrowed it down to two: a 160L Fisher & Paykel chest rated at 307kWh/year, or a 180L Westinghouse upright freezer rated at 297kWh/year. Westinghouse looks better for us other than being imported from China. So what about the fridge?

Given our simple criteria, there was no contest. Absolutely hands-down, the winner is a brand-new model from Electrolux. A 400L upright single-door fridge that uses just 250kWh/year and it's made here in Australia. This product has the highest energy efficiency score of all 3000 refrigeration units in the database, bar none (it'd score 8 stars, but the ratings only go to six). Price is middle-of-the-range: more than the Asian products and less than the European.

So that was the plan. The Electrolux fridge and the Westinghouse freezer. Combined rated total of 547kWh/year, which is just a smidge under 1.5kWh/day.

Er, hang on. I'm going to spend a couple thousand dollars on the most energy-efficient appliances I can find and still only cut my power consumption by 25%? Admittedly I'd have room for a bit more ice cream... but... only 25%? There's gotta be a better option.

Turns out there is, if I can live with just a single six-pack in the fridge at any one time. Another member of the new Electrolux range is a fairly conventional-looking bottom-mount fridge/freezer. 359L fridge space, 156 in the freezer (more than our old one), and a rated energy use of 428kWh/year. That's good enough for a five-star badge, and it's made right here down under.

So I saved myself a few hundred bucks and improved my energy reduction from 25% to over 40% (based on rated consumption of the new fridge vs actual consumption of the one I had). The fridge was delivered today. Now all I have to do is convince Michelle that going from 120L to 156L really is a significant improvement in freezer capacity and we didn't really need a separate freezer anyway.

Yeah. Wish me luck.

Welcome to my backyard

Some pics for a change.

First up, my mostly-recycled chook pen... with a little addition on the near side which I'll get back to in a minute. The far end is the existing fence. Rear-left is a piece of lattice which some previous owner left lying around this place. Rear-right and the lower half of the front and front-left are rigid mesh fence pieces Mr S had in surplus. The gateway on the right used to be parts of Mr S's neighbour's verandah, while the gate frame itself is cut down from a wardrobe door which I hated. Underneath most of it are old hardwood sleepers which were somebody else's idea of garden borders. The only significant new material was the chicken wire to fill in the gaps above the fence panels and in the gate section.

The hutch doesn't look like much in this pic but by damn it was the hardest part of the job, and is also made from recycled materials. I'll post on it another day.



Right down there in front of the home for chooks is the home for my Jericho beans. Six little sprouts now have a chook-proof, well-nourished, sunny spot with lots of opportunity to climb. You can see in the previous pic the passionfruit vine which has its roots in the neighbour's yard. I'm enjoying that for now but will probably cut it back later on to make a bit more room for the beans. More recycled fence panel, a bit of the wood panel from that hated wardrobe door and even some old White Pages went into the construction of this bit. I confess to buying the compost from the hardware megastore today, but at least it's organic.







And finally, some proof that my back yard is actually capable of supporting some kind of useful plant life: our herb garden. Featured are basil, parsley, chives, chillis, rosemary, sage, marjoram, chickory, spring onions and - if you zoom in and look really carefully - a solitary coriander leaf. Yeah, the garden hasn't yet proved it can support coriander. We have some oregano on stand-by to take its place.

The meter goes backwards

It's been a long time coming but we finally have a 1KW photovoltaic array on our roof. Too much detail to post via iPhone keyboard... but I watched our meter turning the other way this arvo. Way cool.

Heeeere, chook chook chooky!

We want chickens.
Chickens need somewhere safe to live and lay their eggs.
I avoid buying new materials.
I pretty much refuse to use concrete.
I use hand-powered tools whenever it's an option.
There was some junk lying around the yard and the shed.
My mate (Mr S) had some even cooler junk in his yard.
We're not stuck-up about the appearance of our garden.
It's a work in progress.
I'll post some pics once I complete the walls.

High Tech, Low Power and Less Nasty

I have deliberately kept my work and my blog separate. The high tech company I work for has a very strict policy about the way employees represent it in public and it's a line I never want to cross.

Suffice for me to say, my employer has just released a new model of ultra-portable no-compromise laptop computer. It has a full-size screen and keyboard, runs the full version of our latest operating system, uses a fully modern Intel processor... and according to the published specs has an average power consumption of just 8W. Yes I have a tradition of liking this company's products but that little stat particularly impressed me.

It's also nice to see attention given to things like the materials choices (making use of aluminium for its recycling value, eliminating PVCs and BFRs etc) and packaging (smaller packaging increases transport efficiency, materials also selected for recycling).

And the best thing is that it's not just my employer who's doing this - lots of other companies are making actual improvements in their environmental impact. I wonder how far they can go with it by 2050.

Pipes and Pumps, part 1

Can you think of a more boring-sounding subject? There wouldn't be too many, but if you care about energy and water efficiency then there are some very important things to know about pipes and pumps. As with many lessons in life, I learned these things shortly after the precise moment when it would have been most helpful to know them.

The context is, of course, that having installed tanks to capture the rain that falls on my roof I needed some way to get that water into my laundry and toilet in order to reduce my consumption of externally-supplied water. In this time and place carrying water in buckets is not an acceptable solution. Pipes, valves and a pump would be required. In this post I'll show you the solution we installed.

As I've mentioned more than once, our two tanks are situated one at each end of our house and are connected by a 25mm plastic pipe at ground level. That pipe has two functions: it allows the water level to rise evenly in both tanks regardless of how much water flows through their respective downpipes, and because it runs straight past the laundry it allows water to be drawn evenly from both tanks through a T piece inserted at the appropriate point. So far so good.

Knowing my limits, I paid a professional to supply and install the rest of the solution. We had a brief discussion about my requirements, agreed to use a pump at the low end of the price/performance curve and arranged to install four taps: one on the outside laundry wall adjacent to the pump, two just inside the laundry for the tub and the washing machine and the fourth a few meters along and through the wall for the toilet.

Stop! Camera time. In this first image you can see the inlet (low foreground) going into the pump body (red). On top of the pump is the electric pressure switch (blue) which turns on the pump whenever the outlet pressure drops below a preset level. The water flows upwards through the pressure switch and out the top.


Here you can see the new pipework (black) going up the wall to the new tap (left) and still further up then through the wall into the laundry.


Next, a shot inside the laundry with the double tap arrangement for the tub and washing machine.


Finally, our modified toilet. My original plan was to have a second tap in the toilet just as we have in the laundry so that we can connect the cistern to the appropriate one as required. The bloke we hired to do the installation explained that council regulations wouldn't allow it - something about making it too difficult for the elderly or the disabled to ensure reliable toilet operation - and so we now have a permanent dual-float configuration where we merely need to turn on the appropriate tap. The tap (and float) on the left control the existing mains water supply while the parts on the right take water from the pump.



Now I shall be the first to admit that, overall, this isn't a "pretty" job - because that really wasn't a goal. The pump gets hidden under a plastic cover that's about the same colour as the concrete, the laundry is destined for eventual renovations anyway and the whole lot is down the back side of the house where nobody goes looking for aesthetic satisfaction.

So that's what it looks like. In the next post I'll go into how well it works.

Water under control

A couple of weeks back I was shocked to see that over a ten day period our water use had shot up to 507L per day, on average. Since then we've renewed our vigilance and made a real effort to get water use back down to where it had been.

The results are satisfying. For the two weeks ending this morning our average consumption is back down to 320L per day, which is slightly better than where we were tracking before.

Helping the cause is our new Shower Saver. I can't imagine using it much in winter, but what a brilliant idea this is. Every shower should have one.

Also, our water tanks are full and overflowing! With all the recent rain there's not been much need for outdoor water use, so I'm eagerly awaiting a call from a mob to come and quote on installing a pump and some internal taps for the toilet and washing machine. I'm really looking forward to seeing how low our mains water consumption can go once those are hooked up.

A productive day!

1. Tank interconnecting pipe fitted: check.
   
2. Overflow outlets fitted and sealed: check.
   
3. Water level gauge fitted and calibrated: check.
   
4. Custom gutter cleaning tool designed and fabricated: check.
   
5. Gutters cleaned, probably for the first time in a decade: check.
   
6. First flush diverters emptied ready for the next rains to rinse out the dirty gutters: check.
   
7. Beer bottles emptied: check and check.
   

That's everything I'm willing to do myself. From here on I'm paying somebody else to finish the job. We've got overflow pipes to run underground to the street, a pump to install and internal plumbing to be done.

Well actually there's one more thing for me to do, which is to bury the connecting pipe that runs between the tanks. That can wait until after somebody has installed a t-piece in the middle of it for the pump to draw from.

Instead of a rubber... thing... to seal the overflow outlet I bought two 90-degree flanged fittings and just screwed them onto the outside of the tank with silicon to seal them. They point downwards and the insect barriers just pop onto the end of them. More pipe can be attached later to take any overflow safely away.

Gutter talk

Late last night a tiny spit of rain fell on my house. I almost didn't hear it on the roof tiles, and when I checked the weather radar there was nothing more than a few white dots scattered over the map. Even so, I went outside with a torch to see if there was anything noticeable happening with the tanks.

Checked the southern end first. No leaks from the new downpipe and a surprisingly steady stream of water burbling into the tank. Was thrilled at first, until I noticed that the water was actually going all the way into the tank instead of filling up the diverter which keeps that first run of dirty water out of the main tank. Check out the image on that linked page. See the hose that runs from the bottom of the diverter out to the outside wall of the tank? I'd forgotten to re-attach that after working inside the tank yesterday fitting the taps. Bummer.

The tank at the northern end was also being filled, but to my surprise it was doing so much more slowly than the southern one. That didn't seem right because the northern tank gets fed from both sides of the house instead of just one. But at least the diverter was filling up in that one.

This morning there was no trace of rain on the ground but at the northern end water was still trickling in from the gutters. Oh yeah... I really need to clean them out. All the crap in them had acted as a kind of sponge, absorbing the water and then releasing it slowly. More on that in a bit.

The diverter in that tank was completely full, and the water pressure demonstrated that I needed to seal the release valve better: it was dripping lightly and excavating a little trench in the crusher dust. The kids and I emptied the diverter into a bucket used the 20-odd litres of somewhat dirty water on our gardens.

Then I set to work removing the diverter from the southern tank, re-attaching its hose, assembling it all again, and using some plumber's tape to seal up the diverter release valves. So far so good. Now to the gutters.

Our stupid gutters. The roof tiles come right out to within a couple of centimetres of the outer edge of the gutters. There's not enough room for me to get my hand in there. I went to the hardware store this afternoon and bought a cleverly-designed gutter cleaning scoop, but there's not even enough room to get that in there. The gutters at the northern end of the house, especially on the eastern side where we have a shade tree, have better-looking compost in them than what's in the black bin at the end of my yard and I can't clean them out.

Very frustrated. Going to have to craft some kind of L-shaped scraping tool to try and clear some of the crap away before the "thundery rain" the Bureau is forecasting for later in the week. Like I have time for that $#!%.

The Tank Fairy

I've never heard anyone speak of the Tank Fairy, but there must be one because mere hours after sliding tank #2 onto its base both tanks have been fitted with taps and hooked up to the downpipes - almost as if by magic!

I'd better stop with the fairy story or my very good neighbour, the actual worker of magic here, might get offended. Around the same time this morning as I was typing my previous post I noticed that Pete had come home. Pete's a builder and I wanted to get his advice about the next steps to take with the tanks. My thinking was that I had to get the overflows hooked up before I did anything else, and that's a big job.

Pete had a different opinion. He reckoned we'd be pretty damned lucky to get enough rain to cause any overflow at the moment and if there was it would be welcome on the garden. So he got stuck into the job of hooking the tanks up to the gutters.

We cut holes for the overflow of course, and I'm about to go and seal them with tape to prevent insects getting inside. We fitted the main valves at the bottom ready to be connected to each other and eventually the pump. And we fitted bucket taps about 40cm off the ground to allow general outdoor use of the water without the need for a pump at all, providing the water level is high enough.

I ordered a simple gauge which will make it easy to tell how much water's available.

Getting the interconnecting pipe fitted is the next priority - especially so since I decided to give up on connecting the southern tank to the downpipes at the front side of the house. There was just too much mucking about required so it's ended up only being attached to the rear corner. That means the northern tank will get about twice as much inflow as the southern one: I need the pipe in place to allow the water to distribute itself evenly between the two.

Is it worm breeding season?

I took a peek in my worm farm this morning. Oh my gosh there are a lot of baby worms in there - roughly the thickness of a dressmaking pin and upwards. At least I hope they're baby worms and not some other kind of worm which shouldn't be there. Not to worry, this is an experiment after all.

The lower chamber looks to be almost completely consumed (ie converted to poo) and there's the beginnings of a good layer of castings in the upper chamber too.

After several months of feeding them not much at all, it seems like I now need to step up the pace a bit. Michelle went to a Tupperware party last weekend and ordered a little gadget which might come in really handy for this, though I'm sure that wasn't what she had in mind. More on that one after it's delivered.

Sunshine on tap

True to their word, the Solahart mob came and installed our new water heater today. The tank was only filled mid-afternoon so it's not had a chance to capture much sun yet and the water coming out of the tap is merely tepid. We've got the electric booster switch turned on tonight so that we can have a shower in the morning, but hopefully tomorrow night the kids will be enjoying the warmth of the sun after dark as they take their bath.

He was only 19... now where's the new kid?

There was a death in the household today. Finally!

Our hulking great electric-storage hot water system sprung a leak this morning after spending 19 years turning one of the most useful forms of energy into one of the least. Hooray and good riddance.

It was a bit of fun in a way. The silly thing was installed inside (presumably so we didn't lose too much heat during Brisbane's biting winters...?) which meant that a sudden leak was something of an emergency. Had to try and shut off the water coming into it and hold open the valves to let as much water as possible escape through the overflow pipe instead of onto the laundry floor. Then discovered that the inlet shut-off tap, which probably hadn't been used in nearly 20 years, just didn't work. The only way to stop the water from flowing was to turn it off at the mains.

Right about then I called Solahart and booked a guy to come out and see us ASAP, which was originally defined as 4:30pm but ended up being closer to 6 after he forgot and I had to chase him up. Oh well, these things happen. In the meantime I had to restore mains water for all our other needs like drinking and flushing the toilet - I ended up removing the inlet tap completely and sealing off that pipe with a brass cap that set me back the princely sum of one hundred and five cents.

I was surprised in the end by the advice we received and the product we ended up ordering. The bloke said that in a place like Brisbane which gets so much sun you should actually avoid buying the most thermally-efficient solar water heaters because for much of the summer you'll end up with water being heated to boiling point, which means a whole lot of water being released down the drain and being completely wasted. With that in mind and having given due consideration to the orientation of our house and the load-bearing capacity of the roof, we're getting a 300L roof-mounted model from the lower-end "L Series".

Because of the weight distribution it'll be mounted flat on the roof facing slightly north of west instead of on a riser which would have had it facing slightly east of north. To compensate for the reduced exposure to the sun it'll have three collector panels instead of the usual two.

If we're lucky it'll be installed before the weekend.

Giving up the pot

While we're on the subject of addictions...

Just kidding. I'm tired and it seemed funny at the time. This is about plant pots, more particularly their absence.

Some of those little capsicum plants which we grew from fresh seed as a random experiment have really flourished in the recent wet and warming weather. Many of the others were starting to show signs of stress, presumably from overcrowding. Today I decided it was time to try our first bit of in-ground planting.

There's an existing garden bed very near to where the capsicum seedlings have been growing. The previous owner of this house put some effort into improving the soil but over the past two years that bed has been totally taken over by something that might be aloe vera. This afternoon I removed a pile of them and cleared about two square meters of the bed.

On top of that I put a layer of compost - my first significant use of the stuff which I've been brewing up in the back of the yard. Michelle and I transplanted about six really strong-looking seedlings and four more which were the best of the rest from the pot into the compost. Then all around them went a layer of the mulch which I made two weekends ago.

It's pretty simple stuff, really, but apart from some really naive poking about when I was a kid this is the first time I've done anything like this: growing seedlings in a pot, making compost, making mulch, planting out a garden bed. To be honest I'm half expecting the plants to die but that's all fine in the spirit of an experiment.

Thankfully our lives don't (yet?) depend on a good capsicum harvest in the back garden. But with a bit of luck we'll have some of our favourite salad fruits from our own crop on the table and the BBQ this summer.

And while we're outside...

I snapped a few more pics around the back yard to show you.

First, some actual news: I GOT ONE OF MY TANKS IN PLACE! It's amazing to see it sitting there so neatly and to think back through the amount of effort that's gone into converting a garden bed full of lilies (which I dug out and kept), manure-enriched soil (which I dug out, sieved and kept) and a tree (which I chopped down, dug out and eventually mulched most of) into the besser brick and crusher dust base on which it rests.

The other end of the house isn't quite so satisfying yet. Oh well.

I've mentioned once or twice that to help reduce the amount of solar heating on the western side of the house I installed some shade screens. Initially it was just in front of our bedroom window (the middle screen in the photo) but it made such a difference I bought two more for my study (nearest) and what is now Asha's bedroom. Am considering one or two more for the other end of the house but we never really notice much heat coming through the walls up there.

Last thing to show you is what we've got growing. All in pots so far as we're just getting started and haven't prepared any permanent beds yet.

In the first pic we have two rows of carrots (can you tell that 5-year-old girls were responsible for "lightly sprinkling" seeds along the centre?) and a whole crowd of capsicum plants plus a seedling pot from which a bean vine will hopefully emerge soon.

The second pic is the three cherry tomato plants in their climbing pot, looking a bit battered after the wild weather this week but covered in green berries and still flowering.

Finally our three little strawberry plants which were given to us by one of Michelle's scrapbooking friends.

Progress on the tanks

This weekend I finally got the second and third sides of the in-ground brick border done for the first of my two tanks. The third side is visibly straighter and more level than the second, which in turn looks positively professional compared to the first. Oh well. They'll do the job. That is, if I ever get it all finished - which at this rate is a bit of a concern.

There were a couple of interesting things that came out of today's work. First, I now not only know what a cold chisel is but have purchased and used one so that a brick can butt up smoothly against the concrete apron around the house. And second, I'm now aware that when a brick company describes bricks as being 400mm wide and 200mm high, that includes 10mm of non-brick (ie, empty air) in each dimension to allow for the concrete which typically is found in between each brick. Of course my brickwork includes no concrete and so the result is not quite what I had expected it to be.

Am pleased to note that the advertised width of the brick includes no non-brick components.