Previous Updates - The Greeny Flat Experience

Apr 22, 2014: Earth Day marks the start of one year of monitoring

Today is Earth Day which seemed like a fitting occasion to begin monitoring the performance of the Greeny Flat experiment. So for Earth Day next year we’ll host a get-together on site to present the results which will hopefully prove that the Greeny Flat has made more energy that it has used over a full year while providing a comfortable and healthy indoor environment and only using a small amount of town water.

We now have the solar power system installed and running and we have a wonderful gadget called a Wattson meter sitting next to the kitchen which shows us how much power we’re making, how much we’re using, and the net amount of power going to or coming from the Grid at any time. It’s fascinating to see how things change at different times of the day and when we turn different appliances on or off. We already knew that it would be the things that use electricity to create heat that would use the most power but it’s amazing to see just how much the electric kettle and the stove consume when they’re on. We’re already figuring out ways to use more power during the day (when the sun is shining and we’re generating electricity) rather than at night. This won’t affect the overall balance of power over the year but it will affect our electricity bills because we are paying 26 cents for the power we take from the grid but only getting 8 cents for the power we export to the grid. So the more we can use our own solar power the lower our bills will be.

Solar power system installed on the garage

Wattson meter showing that we’re making 2.245kW

The main thing we’re hoping to prove is that the Greeny Flat can be energy positive over a year. In other words it should make more power than it uses. In order to be able to prove this we have two electricity meters installed (see photo below). The one one the left labeled “Import” measures how much power we are drawing from the grid and the one on the right marked “Export” measures how much power we put into the grid from our solar system. As you can see, at the beginning of our year of monitoring the Import meter is reading 31kWh and the Export meter is reading 79kWh. So we’re off to a good start since we’ve already made more than twice as much power as we’ve used. On Earth Day next year we’ll read both meters again and subtract these initial readings in order to calculate how much power we’ve used and how much we’ve made.

Import and Export meter readings at the start of the monitoring period. Earth Day, April 22nd, 2014.

We also have two water meters, one to measure how much rainwater we use and one to measure how much town water we use. Our hope is that, by the end of the year we will have used more rainwater than town water. Of course this will depend entirely on how much rain falls over the next year but once again we’re off to a good start having used only 725 litres of town water and 4307 litres of tank water (see photos below).

Two water meters to measure town and tank water use.

Apr 22, 2014: town water meter

Apr 22, 2014: tank water meter.

The other main thing that we want to prove is that the Greeny Flat can stay comfortable even though it doesn’t have a heating or cooling system installed. In order to do this we have installed a data recording weather station that measures and records the indoor and outdoor temperature and humidity as well as wind speed and direction, light levels, barometric pressure, and rainfall. We will be able to download all of this data to computer and display it in graph form. It will be fascinating to compare the weather data with comfort levels and power production and consumption. It’s also pretty nice to have this display that shows the current indoor and outdoor conditions as well as this amazing solar powered outdoor unit that looks like a mini spaceship.

Weather station display panel.

Solar powered weather spaceship.

So that’s all the monitoring equipment we’ve installed so far. We’re still waiting for the solar hot water system to arrive and I’ll be curious to see how we can monitor what it’s doing. Meanwhile we’ve got plenty of new toys to play with as well as plenty more work to do to actually finish the Greeny Flat. Who know’s, by Earth Day next year we might have it done.

Mar 24, 2014: start of a big week

This is going to be a big week on the Greeny Flat project. Cintia and I have to be out of the main house by the end of the month (next Monday) so the Greeny Flat has to be ready to occupy by the end of the this week. Luckily the council will allow us to get an “Interim Occupancy” certificate which means that we can move in before everything is completely finished. The basic health and safety items as well as the BASIX requirements have to be installed but I will be able to take me time finishing the rest once we are in.

George and Daniel did a wonderful job last week installing the skirting boards. After much deliberation we finally decided to go with an aluminium flat bar which was relatively inexpensive (about $4.50/m), installed quite easily, and looks great (I think).

Mar 24, 2014: aluminium skirting boards installed

Today it was raining cats and dogs all day so we set up a tile cutting workshop on the back porch and managed to install about 2/3rds of the tile on the bathroom walls. I finished laying the floor tiles yesterday. The floor tiles we picked up from the Moss Vale Recycled Building Materials yard but the wall tiles we got from Bunnings. I think the combination is going to look great when it’s finished.

Mar 24, 2014: tiling the barthroom walls

The main things we’re trying to get done this week and the plumbing and electrical installations. Once the tiles are grouted in the bathroom we’ll be able to install all the plumbing fixtures. The solar PV panels are due to be installed on the garage on Friday. And we’ll be trying to get most of the electrical work done over the next few days.

Looks like I’ll be as busy as a one-legged man in a kicking contest.

Mar 7, 2014: BASIX is a JOKE!

I was pleased to learn from our local building inspector that we can obtain an Interim Occupancy Certificate (I’ve been lived in Montana for twenty years so I’m still getting reacquainted with how things work here at home). This means that Cintia and I will be able to move into the Greeny Flat as soon as we have the basics installed, i.e. some way to wash and cook. BUT she also said that we have to have all of our BASIX commitments installed.

For anyone reading this who is not from around here, BASIX is the Australian Governments ‘Building Sustainability Index’ which requires that every new development complete an online sustainability assessment and commit to installing certain things like so much insulation, double-glazed windows, rainwater tanks, solar panels, etc. When I submitted the initial application for the Greeny Flat to the Wingecarribee Shire Council I had to include a BASIX certificate. In my proud and passionate fervour about the Environmentally Sustainable superiority of the Greeny Flat project I included everything I could think of in order to get a really good score, which I got. In fact on the energy side, where the pass mark is 25% (25% of what? You may well ask but I can’t answer. Whatever it is though doesn’t 25% seem pretty low?), we scored 98%! The fact that I have no idea what I’m scoring 98% of doesn’t matter, does it? I was pleased as punch.

Trouble is, I want to move into the Greeny Flat before I have installed everything that I included on the original BASIX certificate (like ceiling fans, kitchen exhaust fans, etc). So now I have to redo the BASIX certificate and uncommit to those things. So I jumped online early this morning and went through the assessment again and, just for fun, I took out everything that wasn’t already installed (or committed to, including the 3kW solar PV system) and I still scored about 80% for the energy performance. This got me curious so I went through and took out everything I could think of down to uncommitting to install compact fluorescent light bulbs or any solar power at all. At this point I finally failed. Then I added back just enough solar power in order to pass again… i.e a 0.6kW solar power system!

What a joke! Admittedly the Greeny Flat has a significantly better Thermal Envelope (insulation, air-sealing, double-glazed windows, etc) than your average house. Nevertheless, what this means is that, in order to pass the Australian Government’s BUILDING SUSTAINABILITY INDEX (sounds grand doesn’t it), all I had to do was put in a tiny solar power system… nothing else!

This confirms what I already suspected… BASIX is meaningless and just another beaurocratic hurdle to jump over. I come back again and again to thinking that what really matters is that we learn how to use as little energy as possible and make more renewable energy than we use. So, after I resubmit my BASIX certificate to the council, we will not be committed to doing anything much on paper. In reality we remain deeply committed to the goal of building an energy positive home at an affordable price.

Mar 6, 2014: starting on the kitchen

After looking at many different options for pre-manufactured kitchen cabinets we finally decided to do it the old-fashioned way and just build the kitchen ourselves in-situ. We have an old, reclaimed kitchen sink, the kind with a lip at the back that turns up behind the backsplash so that water can’t penetrate the benchtop (like it can, and often does, with drop-in sinks). Apart from that we’re making the rest up as we go along. All we really know is that we want to use structural pine, Ecoply, and sheet metal (gal or zincalume) for the materials and Mum has figured out a basic layout. The rest is a lot of head scratching, trial and error.

Mar 5, 2014: starting the kitchen installation

We also started running the conduit for the surface-mounted electrical system (see photo below), something else that we’re having to figure out as we go along. I have to say it’s pretty exciting to be working on the finishes, particularly as we’re in uncharted territory. It’s fun to see how the details come together.

Mar 5, 2014: conduit and mounting block for light switch next to front door.

Mar 1, 2014: Pumps and Solar Hot Water: decisions, Decision, DECISIONS!

I’ve often said that there must be a million decisions made in the building of even the smallest, simplest home. Some are small and quick like deciding where each screw is placed in a sheet of plywood. Others are big and tricky like deciding what sort of floor, wall or roof system you’re going to use, or what sort of windows to buy. This last week has been a week of fairly significant and difficult decision making (or not making, as the case may be).

Solar Hot Water: I originally had in mind an evacuated tube split solar hot water system from Apricus Australia. In a split system the panels are on the roof but the tank is either on the ground outside or, in our case, in the storage attic above the bathroom. But this was complicated by a number of factors. First I was told that the available storage tanks wouldn’t fit in the available attic space. Then I had a bloke from Dux tell me that flat plate panels are not only more durable than evacuated tubes but are also more efficient, even in low-light conditions. This was the first time I’d ever heard that flat plates performed better than evacuated tubes so I asked him to send me more information. The document he sent is Dux advertising that makes lofty claims but doesn’t provide any information to back it up (click here to view the pdf). This is completely contradicted by the following Wikipedia page which accurately states that it is very “difficult for purchasers and engineers to make informed decisions.” I’m waiting for the Dux guy to get back to me with more information. Meanwhile Paul from Tempco in Bowral told me that after installing hundreds of solar hot water systems in this area he is now recommending that people put in a heat pump water heater and solar PV panels instead. So we haven’t made any decision yet but we’re looking at two main options. One is back to the Apricus Evacuated Tube solar system because Paul informed me that they now make a smaller (160lt) tank that will fit into the attic space that we have. The other is a split Air-source Heat Pump water heater from Sanden Australia. This systems looks pretty promising too and is the only “split” heat pump water heater I’ve seen (i.e. the compressor that usually sits on top of the tank is a separate unit so it can be outside and the tank can be inside). It claims to be super-energy-efficient, very quiet, and also has the option of a 160lt tank which would fit in the attic. I’m waiting for more information and costing for both of these possibilities but leaning towards the solar because it’s quieter and has fewer moving parts.

Evacuated tube solar panel (click on image to visit Apricus’s website)

Split air-source heat pump water heater system (click on image to visit Sanden’s website)

Rainwater Pump: After lengthy research and discussions with a number of technical advisors we did manage to make a decision and order the pump for the rainwater tank. The main factors that we were considering were reliability, noise and what sort of switching device. This is an elegant little device that allows us to use tank water whenever we have it and automatically switches the entire system over to town water when the tank gets low. Click here if you’d like to read more details about this exciting decision but to sum it up we settled on a CNP-CHLF2-30 external centrifugal multi-stage pump with a Bianco “Rainsaver” switch from Southwell Irrigation who have provided reliable equipment and service to my parents and their Kangaloon property for many years. They also gave us a very nice discount so the final cost for both the pump and the Rainsaver was $852, more than we had budgeted but I feel confident that this is the right equipment for our needs.

Other things I’ve been researching and trying to decide on this week are exhaust fans for the bathroom and kitchen, ceiling fans, light fixtures, plumbing fixtures, door hardware, and exactly how to make our surface-mounted electrical system. More about these fun things soon.

Feb 24, 2014: Greeny Flat in the news

We had a very pleasant visit last week from Megan Drapalski, a reporter with the Southern Highland News, and we were honoured to find the following article in the local paper today. Thanks Megan, for a nice article that accurately and succinctly explains what we’re up to.

http://www.southernhighlandnews.com.au/story/2106786/greeny-flat-minimises-energy-bills/?cs=261

Feb 20, 2014: surface mounted electrical system

We’re nearly finished installing the plywood on the interior walls. I’ll try to post some pics this weekend.

Meanwhile I’m working on figuring out the details for the surface-mounted electrical system. Basically we’ll run a hollow “picture rail” around each room above window and door height that will carry the wires for the power and lighting circuits. Then wherever we want a switch, powerpoint or light we’ll run a conduit up or down the wall to the required height. The point of this system is that in the future we’ll be able to make changes as needed without having to tear into the walls. When you have a house with no attic and no crawl space it’s very difficult to make changes or repairs if everything is hidden inside the walls.

Feb 19, 2014: end in sight for the construction phase.

Today my brother George was busy putting up more plywood on the interior walls and I spent most of the day researching water pumps and setting up this website. Then it rained which was nice because we laid some turf last week and it needs a lot of water to get it established. It’s a very hardy type of grass that won’t need much water when it’s mature but rain is perfect for it right now.

I’m guessing we’re about a month away from having the flat complete enough to where Cintia and I can move in. There’ll still be some minor details to finish but we should be able to get our occupancy certificate from the council. That will allow Mum to rent out the main house again (we’ve been living in the front house while we’ve been building out the back) and we’ll be able to start the next phase of the experiment… living in the flat and monitoring how it actually performs.

This is something that is very seldom done by the people who design and build buildings. They almost never go back to see how things actually work and so they seldom learn from their mistakes. I’ve learned an amazing amount through the planning and building phases of this project so far. And I expect to learn as much again from carefully monitoring its performance for at least the next year. And by living in it myself I’ll find out the little things that work well or don’t work. Hopefully I’ll have a chance to fix or at least improve the ones that don’t but I intend to be honest about them in this blog and not just brag about the cool stuff that does work.

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