April 28, 2017: Doing the Dirty Work

Replacing the sewer lines down the west side of the house next to the Greeny Flat.

Replacing the sewer lines down the west side of the house next to the Greeny Flat.

It’s been a busy week here at the Greeny Flat. We’ve been replacing the sewer lines as part of the energy retrofit of the old fibro cottage on the property. For new readers, you can catch up on the progress of this project via a series of short YouTube videos we’ve made over the last seven months. CLICK HERE for links to all the videos.

I’ll try to find time to make a new video next week with an update. We’ve now got our Solar Air Heater up and running, we’ve added paving down the south side of the house to help deal with moisture issues, and we’re getting ready to build a deck and awning on the west side to help keep the house cool in summer. This is what has led to the sewer line replacement, because the deck will be built over the top of where the 70-year-old earthenware sewer pipes were buried. This will make it quite difficult to fix them later in the future so we thought it would be wise to upgrade them now while we can get them relatively easily.

As you can see from the photo above, it was a dirty day’s work but it all went well and we’ve now got the back yard back into reasonable shape and ready to start work on the new deck. More on that soon…

Ban The Bag Update

Following on from last week’s Newsletter in which we encouraged our readers to sign this no-brainer of a petition. I just received the following update from the campaign. So far 120,000 people have signed, including our local legend, Jimmy Barnes which you can read about by Clicking Here.

Wind and Water Power

The Waterlily portable Wind and Water Turbine

The Waterlily portable Wind and Water Turbine (Image source: NewAtlas.com)

I don’t know why it never occurred to me but it seems pretty obvious when you think about it…. a turbine that can generate power from wind could also be capable of making power from flowing water. And that’s just what this new gadget called the Waterlily is designed to do according to this NewAtlas article. It is designed for camping and can deliver 25W of power from either a 7.2km/h water flow or a 72km/h wind.

Personally I’d rather go camping in a place where you could make 25W from a small solar panel than somewhere it’s blowing 72km/h. But for those rugged types that like to do it tough (but still be able to power their devices), this could be just the thing you’re looking for.

Australia Needs an Energy Policy

My dear Cintia forwarded me the link to this story from The Guardian which claims that Australians could save $100bn if we had a clear and comprehensive national energy policy.

The report’s estimated $100bn in cost savings is a function of governments rolling out nationally consistent policies that would encourage the two parts of the system to work harmoniously together – the current poles and wires of the national market, and the virtual grids in homes and businesses. Allowing efficient co-optimisation would prevent overinvestment in poles and wires.

Photo by Andy Leman

Photo by Andy Lemann

Ironically, the same policy could facilitate the transition to a clean energy future.

The report suggests by 2030, around 40% of generation could come from renewable technologies in Victoria and Western Australia, with an increasing share in New South Wales and Queensland as coal generators are retired.

But the report points out that the massive technological transformation is rolling out in a policy vacuum.

“There is currently no enduring, clear long-term climate policy. There is also a lack of integration between electricity sector planning processes and climate policy,” the ENA report says.

And even more remarkably, the article reports a major swing among a wide spectrum of industries back to the idea of some sort of market mechanism to reduce carbon emissions.

A string of peak bodies have used the review to call for the adoption of a market mechanism, including the National Farmers’ Federation, the Investor Group on Climate Change and the Business Council of Australia, which explicitly called for an emissions intensity scheme.

The current industry consensus around carbon pricing is a major turnaround in a very short period of time.

Three years ago some of the same groups urged the parliament to get out of the way so that Tony Abbott could repeal the Gillard government’s “carbon tax”.

Another Blow to the Adani Mine

The final piece of good news for the day is that Westpac has finally ruled out the possibility of providing funding to India’s Adani Coal Company to build Australia’s largest coal mine in the Galilee basin in Queensland.

In our Newsletter two weeks ago I wrote about Malcolm Turncoat’s offer to provide a billion dollars of taxpayer money to help Adani build a railway line from the mine directly to the Barrier Reef where the current coal stockpile recently contaminated a sensitive wetland.

The other three big banks had already ruled out funding the mine but Westpac was dragging their feet. So it’s good to know that ‘the world’s most sustainable company‘ (that’s Westpac by the way, no joke) is now unwilling to back this massive fossil-fuel project.

April 21, 2017: Ban the Bag

Tomorrow is Earth Day and, as detailed in our April 7 Newsletter, we’ll be hosting our 3rd Earth Day party at the Greeny Flat (16A Queen St, Mittagong) from 4-7pm. Everyone’s welcome. We’ll be cooking pizzas and we’re asking people to bring something to drink and a bit of finger food to share. Hope to see you here tomorrow!

Petition to Ban Single-use Plastic Bags

I know… I’m getting a bit political again… but this one’s a no-brainer. There are only three states in Australia that don’t have an existing (or pending) ban on single-use, non-biodegradable plastic bags. They are NSW, Victoria and WA. This new petition on Change.org seeks to remedy that by calling on the premiers of all three of these laggard states to catch up.

Imaged sourced from 'The Truth About Plastic Bags'

Imaged sourced from ‘The Truth About Plastic Bags

In case you still need convincing that this is a good idea here are a couple of quotes from the petition web-page:

‘Australians use an estimated four to six billion plastic bags each year. That’s 10 million bags every day. Every minute, we send 7,150 plastic bags to landfill. But 80 million plastic bags never make it to landfill, and instead end up in our litter stream, killing 100,000 birds and marine life every year.’

‘On average, it’s estimated we use a single-use plastic bag (like you’d find at Coles and Woolies) for just 12 minutes. And that same bag could take up to 1,000 years to break down.’

It only takes a couple of minutes to sign the online petition which, in just the first two days, has already been joined by over 91,000 people. So please CLICK HERE to sign up and help spread the word.


April 14, 2017: One Down, One Billion to Go.

Earth Day Party

First up this week I’d like to remind everyone that we’re having our 3rd Earth Day Party at the Greeny Flat on Saturday, April 22nd, 4-7pm. You can read all about it in last week’s Newsletter here.

One Down – Hazelwood is Dead



The good news for this week is that one of the world’s most polluting coal-fired power plants, the Hazelwood power station in Victoria, is now closed. You can read more about it in this ‘Energy Matters’ article which states that the plant was responsible for about 3% of Australia’s Greenhouse Gas Output along with an annual dose of:

  • about 15 million tonnes of CO2
  • 25,000 tonnes of nitrogen oxides
  • 14,000 tonnes of sulfur dioxide
  • 7,700 tonnes of hydrochloric acid
  • 74 kg of arsenic
  • 140 kg of lead
  • 4,800 tonnes of fine particulate matter
  • 6,900 tonnes of carbon monoxide
  • 440 kg of mercury

This is great news for the environment. I just hope that the poor governmental planning surrounding the closure (we’ve known this was coming for years) doesn’t destabilise our electricity grid to the point where we do crazy things like the following.

One Billion to Go – Turncoat Offering Taxpayer Money to Help an Indian Company Destroy the Great Barrier Reef.

How do you begin to describe the insanity surrounding Adani’s proposed Carmichael Coal Mine. We know we have to stop burning fossil fuels. We know the Great Barrier Reef, one of the most beautiful and beloved ecosystems on the planet, is in a state of collapse. We know our government is withdrawing funding from social services and yet our esteemed Prime Minister Malcolm Turncoat is over in India offering to use $1 Billion dollars of taxpayer’s money to help build the biggest coal mine in Australia, stockpile the coal near sensitive wetlands and ship it through the Great Barrier Reef.

170414 Carmichael map

The Abbott Point Coal Port is right next to the Great Barrier Reef

Just this month we had a timely and tragic reminder of the madness of this scheme when Cyclone Debbie caused a massive release of coal-laden water into sensitive wetlands next to Adani’s coal stockpile at the Abbott Point Port.

Abbott Point

Satellite photos of the Caley Valley wetland next to the coal stockpile at Abbott Point before Cyclone Debbie (left) and after Adani released a huge amount of coal-laden water (right).


As reported in this article on The Guardian;

‘A vast swathe of the Caley Valley wetlands has been blackened by coal-laden water released from nearby Abbot Point port after Debbie’s torrential rains inundated its coal storage facilities last month.’

Join the Fight

Here at the Greeny Flat we try to avoid politics as much as possible. The only trust I have in politicians is that they will serve their own interests every time by doing the bidding of whoever gives them the biggest political donations. I don’t belong to, follow or believe in any political party, in fact I think party politics goes against the whole idea of democracy. But I can’t sit by and watch this outrageous injustice be committed against the future inhabitants of this beautiful planet and do nothing.

So I have joined the Australian Conservation Foundation’s fight against the Adani mine. I urge you to look into the facts, decide for yourself and take action to help stop this if you agree with my view that it is an abomination.

Here endeth the rant.

April 7, 2017: 3RD EARTH DAY PARTY – April 22

Earth Day Party photo

Saturday, April 22nd marks the global celebration of Earth Day as well as the end of our third year of living in and monitoring the performance of the Greeny Flat. Hopefully the rain will stay away or we might be packed in like sardines as we were for our first Earth Day Party (see photo below). But, come what may, we’ll be opening our doors from 4-7 pm and welcoming anyone who would like to come and see how the Greeny Flat is looking and performing after three years.

Friends helping us celebrate our First Earth Day Party on April 22nd, 2015

Friends helping us celebrate our First Earth Day Party on April 22nd, 2015

It seems to be becoming a tradition for us to cook home-made pizzas for everyone, so we’ll do that again. Feel free to bring something to drink along with either an appetiser or a dessert (finger food is great to limit washing up). We look forward to celebrating another successful year of life in our energy positive house. As you can see from our Results Page, we continue to export more than twice as much power to the electricity grid as we import from it. Even though we’ve had our Plug-In Hybrid Electric Vehicle (PHEV) for over a year now and been plugging it in every day to charge the batteries we continue to be well and truly energy positive. This is very exciting for us. It means we’ve been able to reduce our carbon footprint even further by doing a lot of our local driving using renewable energy instead of petroleum.

We hope to see you here on Saturday, April 22nd to help us celebrate our great good fortune and our wonderful community of friends…. not to mention the following…

Greeny Flat Featured in Highlife Magazine

Screenshot from the Highlife website.

Screenshot from the Highlife website.

Thanks very much to Deborah McIntosh, the editor of Highlife, for a very nice article which appears in the current edition of the magazine and to Tony Sheffield for some wonderful photos (like the one above). Speaking of Tony, if you like nice photos of the area and/or old maps, I would encourage you to check out Tony’s gallery which is at the back of the Brown Bookshop, 311 Bong Bong St, Bowral. Tony takes badly worn old maps and restores them to beautiful condition and his photos are charming.

Another local couple who were also featured in this edition of Highlife are Deb and Jacob Newman from the Eden Brewery. I wrote about this new, local, green brewery in our Newsletter on January 13th, which was the day they opened. Since then they have been going great guns and are just managing to keep up with the demand for their delicious brews. They are now on tap at the Mittagong RSL Club, the Hunger Therapy restaurant and the Imperial Hotel in Bowral, and soon to be in a number of other local venues.

I’m particularly excited to try their special Anzac Beer which will be available from next Wednesday. Deb tells me that Jacob put together the recipe for a big vat of the brew and then chucked in 400 Anzac Biscuits to give it a special taste for the occasion. Jacob told me today that he thinks it’s going to be really good. If it’s anywhere near as good as the Irish Stout he made for Paddy’s Day then I reckon I’m going to love it. It will also be on tap at the RSL Club for Anzac Day and available at the brewery at 1/19 Cavendish St, Mittagong. If you haven’t been yet and you like beer then do yourself a favour… they’re open Wed to Sunday, 12-8pm.

Cheers! Andy

March 30, 2017: Electric Shocks

Image source: finder.com.au

Image source: finder.com.au

Are you prepared for significantly higher electricity prices?

I have a friend who works in the solar industry and watches the wholesale price of electricity on the National Energy Market very closely. He tells me that for about the last six months the wholesale price has been double what it was last year. So instead of 4.5c/kWh it has consistently been over 9c/kWh.

I was also contacted for advice last week by a company that has just been told by AGL that their electricity price is going to increase by 57% when their contract comes due for renewal in the next couple of months.

How long do you think it will be before residential customers see similar increases? My guess is, not long at all.

While I know this is going to hurt a lot of people, there’s a part of me that thinks this is the best thing that can happen. For many years now I’ve been saying that the only thing that will make people start to think about how much energy they use (and how to use less) will be significantly higher energy prices. What this will do is 1) make more people and businesses look at how they can improve efficiency and conserve energy and 2) make renewable energy (with storage) more cost competitive in the market. Already solar and wind energy are the cheapest forms of new electricity generation but the obvious problem is that they only make power when the sun shines or the wind blows. Storage is the key to making renewable energy work on a broad scale and there are lots of ways of storing energy.

The obvious one is batteries but we can also use renewable energy to pump water uphill when there’s an excess then let it run back down through a generator when more power is required. This is called ‘Pumped Hydro’ and is what Prime Minister Turncoat is touting as our latest ‘Nation Building Exercise’ (anyone seen Utopia?) in the Snowy Hydro Scheme. By all accounts this is a program that was conceived thirty years ago and has been languishing in someone’s drawer in Canberra due to very high costs and dubious benefits. In the Turncoat version there is very little indication of how much it will cost, when it will be completed or where they will source the power to pump the water up the hill. By some accounts it is, in fact, a fossil fuel project with the plan being to use dirty coal and gas to power this ‘renewable energy scheme’.

There are also plenty of ‘Solar Thermal’ projects in the pipeline which can store the sun’s energy in the form of heat either by melting salts or heating big blocks of pure graphite. Another way of storing energy I read about recently is to use electricity to convert hydrogen into ammonia which can be stored and transported in liquid form (using current LPG and LNG infrastructure) then converted back into electricity via a fuel cell. There are also other forms of chemical energy storage as well as physical ones like using electricity to lift a weight then using gravity to produce power or using excess energy to turn a flywheel which can be drawn upon later for power generation.

For now, batteries are the simplest, most cost effective and most readily available way for you and me to store excess electricity. But before you rush out and put a deposit on a new Tesla Powerwall2 you probably need to know about AS/NZS 4777.1:2016. This is the new Australian Standard for ‘Grid Connection of Energy Systems Via Inverters’ and, according to this article from Finn Peacock at Solar Quotes, it may well make it illegal to install a Powerwall2 on most houses with solar in Australia. This is because most houses have single-phase power and there is now a limit of 5kW of inverters per phase. The Powerwall2 contains a 5kW inverter so you would be fine to install one if you didn’t have any solar but, as soon as you add solar panels (with their required inverter/s) you would exceed the allowable inverter limit.

This is why we need a standard for battery installations!

This is why we need a standard for battery installations!

The image above shows what can happen when a cheap lithium-ion battery explodes and is the reason why there is also a new Australian Standard in the works for Battery Installations. The word I’ve heard is that it will most likely require all batteries (both the cheap exploding kind and the well-built, water-cooled Tesla varieties) to be installed in a fire-proof enclosure outside of homes and garages. This will add a LOT to the cost of a battery installation.

So you could get around the 5kW inverter limit by buying even more solar panels, a couple of Powerwall2’s and going completely off the grid. But, especially with the coming Battery Standard, this is likely to be a very expensive proposition and is a fundamentally bad idea. As I’ve been saying for a long time now, in order to effectively go off the grid you’ve got to install a lot more solar and batteries than you really need (in order to get through a period of cloudy weather). Not only is this expensive but, as soon as the batteries are full, there is nowhere for all that excess solar power to go so it is simply wasted. If we stay tied to the grid we can properly size our systems and any time we have excess renewable energy it can go into the grid and be put to good use by someone else.

If only Mr Turncoat’s government would get behind this idea and make it easy and affordable for people and businesses to do it we could go a long way towards solving our looming energy woes. But for now they seem more interested in propping up the dying fossil fuel industry.

170330 clear solar glass

Meanwhile these guys are propping up some ‘energy harvesting glass’.

On a brighter note (pardon the pun) a reader (and old high school friend) sent me this article from the ABC a couple of days ago about a team based in Perth that has developed the world’s first commercially viable clear, solar glass.

‘We call it energy-harvesting clear glass,’ Professor Alameh said… ‘This is a glass that can pass the visible light through, while blocking the UV and infrared components of the sunlight and routing them to the edge of the glass for conversion to electricity via solar cells placed around the edges of the glass.’

Depending on the cost, this could have promising applications in greenhouses and skyscrapers. If we’re going to build these ridiculous buildings covered in glass and air-conditioned 24/7, at least let’s make them so that the glass produces some energy.

More soon and, as always, thanks for reading.

March 17, 2017: Big Changes Coming

Happy St Patrick’s Day! I have nothing to write about that relates to anything Irish or alcoholic but some of it might be green. This week I want to talk about some major changes that seem to be heading our way and might have a big effect on the way we work, drive, build and live. One is electric vehicles and the other is 3D printing.

I’ve been reading lately that India now has a plan to change it’s ENTIRE car fleet to electric vehicles by 2030. According to this article from Green World Investor, which is based in India…

‘Last year the NDA government proposed a plan to transition to 100% electric vehicles by 2030. It is a huge target set by the Indian government. … The launch of electric vehicles in India will not only reduce the country’s dependence on oil imports but will also help in fighting the increasing level of air pollution in the Indian cities. This will in turn help India achieve its target of reducing the emission intensity of its GDP by 33-35% by 2030.’

It’s amazing to think that India might be contemplating such a revolutionary transition while our ‘Innovative’ Government is still talking about ‘Clean Coal’ and upgrading the Snowy Hydro Scheme. I’ve said for a long time that someone needs to come out with a really simple and affordable electric vehicle. Sure, a $150,000 Tesla would be nice, but most people just need a cheap and efficient way to get from A to B. We don’t need SUV’s with reversing cameras and satellite navigation systems, just something that works. Ideally a small electric vehicle covered with solar panels that can charge itself while it’s parked in the Aussie sun. So it seems to me that, if India is serious about their 100% EV goal, they will be pouring a lot of money and effort into developing really affordable and practical electric cars. This could well put them at the forefront of a huge global market and one day soon, we might all be driving one of these.

170317 Solar EV india

The SERVe (Solar Electric Road Vehicle) from Tata Solar Power and the Manipal Institute of Technology

Of course our ability to afford one might depend on whether or not we still have a job.

I’ve been in the building game for about thirty years and I’ve always been struck by the inefficiency of our western building systems. On the other hand, they do employ a LOT of people. As in many fields where technology and artificial intelligence are taking over and taking people’s jobs, there is a very real prospect that carpenters and bricklayers might soon be replaced by printers.

Here are a few recent articles from New Atlas that illustrate the point.

The Apis-Cor 3D-printed house

The Apis-Cor 3D-printed house

This first article describes a recent project in Russia where this little house was printed in place in 24 hours under a tent in brutally cold weather…‘The machine didn’t do all the work, though. The roof, insulation, windows, and other components were all added later by humans. The total cost for the project came in at just US$10,134, not including furniture or appliances.’

That’s an impressive price for an impressive little building. The two things I don’t like about it are 1) it’s likely to put builder’s like me out of work and 2) it was printed using cement. As you probably know, Portland cement is an environmental nightmare being responsible (by various estimates) for somewhere between 6 and 10% of the world’s carbon emissions. So that’s where the next technology comes in which is all about 3D printing with cellulose.

This next article describes recent work at MIT to develop a new method of using cellulose as the feedstock for 3D printing… ‘providing another renewable, biodegradable alternative to popular petroleum-based polymers like ABS currently being used. The researchers also believe printing with cellulose could be cheaper and stronger than other materials and even offer potential antimicrobial properties to boot.’

Imagine the little house shown above but printed with cellulose so that it is lighter, stronger, better insulated, cheaper and made from a renewable resource. It’s enough to scare the brickie’s smile right out of his pants.

170317 plumbers crack

As Nancy Reagan put it…’Just say no to Crack!’

Add to this the further development of a 3-D printing system that mimics the micro-structure of plants, bones, corals, shells and other natural materials that have very high strength-to-weight ratios as described in this final article….

3-D printed Bio-mimetic structures offer exceptional strength-to-weight

3-D printed Bio-mimetic structures offer exceptional strength-to-weight

And a picture starts to form of a future where extremely light, strong and affordable buildings can be printed on site in a very short time using renewable and highly insulative materials by machines that can work 24 hours a day.

It’s hard to see how our current building industry is going to survive…. maybe that’s not such a bad thing but who’s going to be able to pay for these wonderful buildings when all our jobs have been taken by robots?

Beats me!

March3, 2017: Massive Erections

Did you know that Australians have the biggest erections in the world?

I’m talking, or course, about the size of our new homes.

When they say 'acreage design' they're talking about the floor area.

When they say ‘acreage design’ I think they’re talking about the floor area but if you read the fine print, the good news is that ‘the layout ensures energy efficiency and environmentally sustainable living’…. hmmm, I’m going to call ‘Bullshit!’ on that one.

I’ve written about this before but was reminded again by this recent article from The Conversation just how crazy this is in a country that also has some of the least affordable housing in the world. The following quotes from the article help to illustrate the point.

Over the past 60 years Australian homes have more than doubled in size, going from an average of around 100 square metres in 1950 to about 240 square metres today. This makes them the largest in the world, ahead of Canada and the United States.

At the same time, the average number of people living in each household has been declining. This means that the average floor area per person has skyrocketed from 30 square metres to around 87 square metres.

Results show that larger houses use much more energy, but also that as size increases, the energy used in building and maintaining the house grows by more than the energy used to operate the house.

It’s important to note that the cost of homes as well as the amount of energy they use is typically measured in terms of $/sqm or kWh/sqm. This has the effect of making large houses seem cheaper and more energy efficient because you are dividing the cost and the energy use by a larger number of square metres. It is much more useful and realistic to think about the cost per person or the energy use per person. The following chart from The Conversation article does just that and compares the total energy use over 50 years PER PERSON for different sized houses with different numbers of people living in them. Note that the biggest house uses more that twice as much energy PER PERSON than the smallest house (also note that the smallest house listed is nearly twice the size of the Greeny Flat which we find to be perfectly adequate for two people at 57sqm).

170303 house size and energy per person

Smaller dwellings tread more lightly on the planet and on your pocket.

It is important for developers and architects to provide homes that are better designed for comfort and the environment while still being affordable.

Current energy efficiency regulations don’t account for the energy embodied in building materials, and so fail to adequately capture house size.

Most energy efficiency regulations also only measure energy use per square metre. Using this metric, larger houses appear to be more efficient

The Australian 6-star standard does include house size when considering heating and cooling, but other certifications don’t. Under these other certifications (including the BASIX system used in NSW), a larger house would therefore be easier to certify, considering everything else is constant.

This is ironic since larger houses use significantly more resources, both for construction and operation.

We need to revise current energy efficiency regulations to include embodied energy and other measures of energy if we are to reduce the total energy and broader resource demands associated with buildings.

I absolutely agree that we need stronger regulations. BASIX, which stands for Building Sustainability Index, is a total failure and the proof can be found in the fact that the house pictured in the advertisement, which is enormous and totally inappropriate to our climate with its brick veneer walls, single-glazed windows and black roof, can pass BASIX and is allowed to be built.

Unfortunately, whenever anyone tries to suggest higher energy efficiency standards, the big players in the housing development industry (who have a lot of political influence) jump up and down and scream bloody murder about how higher standards will drive up the cost of housing and make it even more unaffordable.

Well I have a very simple answer for them…. BUILD SMALLER HOUSES!

Feb 24, 2017: PHEV Love

Our PHEV at a remote campsite near Yamba.

Our PHEV at a remote campsite near Yamba.

We’ve had our Mitsubishi Outlander Plug-In Hybrid Electric Vehicle (PHEV) for over a year now and we absolutely love it. We charge it up from our solar panels during the day and do most of our local driving powered by our own renewable energy. We’ve taken it on lots of camping and surfing trips, slept in it, pulled boats with it, hauled building materials and trailers with it… in short it has done everything we’ve asked of it comfortably, quietly, efficiently and economically. We reckon it should be the most popular SUV on the Australian market and yet, hardly anyone even knows it exists. I put that down to an abject failure on the part of Mitsubishi to effectively market a car that would sell itself if people knew about it.

Anyway…. we love it!

So it was nice to read this article from New Atlas which cites a Lifecycle Assessment study comparing a Mercedes E350e (PHEV) to the standard, petrol engine E350. Here’s a quote…

‘According to the lifecycle analysis conducted by TÜV, building, owning and recycling the new E350e emits around 44 percent less C02 than the outgoing E350 CGI, which offered similar performance to the new hybrid, but ran with a conventional petrol engine instead. The testing assumes the car has been charged using a conventional European plug, but also says using renewable energy to charge the battery could improve that figure to 63 percent over the course of 250,000 km.’

Since we primarily charge our Outlander PHEV using our own renewable energy, it looks like our we should see something like a 50-60% reduction in GHG emissions over the life of the car. So not only is it perfect for our needs, it’s significantly better for the planet.

That makes me even happier.

Feb 2, 2017: Every Home Needs This!

I have an idea for a gadget that I think every home could benefit from and that could also help provide valuable data to research organisations like the CSIRO.

Will Sydney beat the heat record tomorrow?

Will Sydney beat the heat record tomorrow?

Right now Sydney is bracing for what is predicted to be the hottest February day on record. Meanwhile we, like every generation before us, live in a house with no air-conditioning. Luckily the Greeny Flat has a number of significant advantages over most of the houses those previous generations grew up in. We have the benefit of understanding Passive Solar Design and how it works to keep a house cool in summer as well as warm in winter. We have an excellent site that is well protected from hot westerly winds and from the late afternoon sun. The Greeny Flat is correctly orientated to allow our roof overhang to shade the north wall and to minimise the amount of wall area exposed to the hot sun from the west. Our windows are also carefully placed to reduce heat gain from the afternoon sun and all our windows have insulating blinds to help keep heat out during the day. The Greeny Flat is clad in a light-weight material that cools down quickly once the sun is off it. It is properly air-sealed and insulated and has sufficient thermal mass to absorb any excess heat during the day and is designed for good cross-ventilation to cool it down at night. And, most importantly, we understand how to operate the Greeny Flat in such a way as to get the best performance from all of the above features.

This is a key point because even the very best Passive Solar house can be too hot in summer and too cold in winter if it is not operated correctly. In the future this will probably be taken care of by automatic devices that do things like open and close windows and blinds at the appropriate time. These things already exist however we are not that advanced. We are still living by the old adage… ‘Passive House, Active Owner’. This means there are certain things we need to do to keep our home as comfortable as possible and reduce our energy use and running costs.

In summer we have to open the house at night to encourage cross ventilation and to cool down the thermal mass and then close all the windows and blinds during the day to keep the heat out and the cool in. The trick is knowing when to open and close the house. To help us with that decision we are constantly referring to two things, one is an online weather forecast (this allows us to know in advance if extreme weather is coming so we can be prepared)

What's the weather going to do for the next few days?

What’s the weather going to do for the next few days?… VERY hot but relief is in sight.

and the other is our own weather monitoring station and in particular the readings for the current indoor and outdoor temperature.

Our weather monitor is currently showing the hottest indoor temp we've had and tomorrow is predicted to be hotter!

Our weather monitor is currently showing the hottest indoor temp we’ve had at 29.2C (and tomorrow is predicted to be even hotter!)

If the weather forecast tells us that it’s going to be a hot day we start watching the temperature readings early in the morning and the MOMENT the outdoor temperature climbs higher than the indoor temperature we close the windows and doors, draw the blinds and turn off any exhaust fans (because when you blow cool air out of a house you also suck hot air in from outside). In the evening we do the opposite, we watch the weather monitor and as soon as it’s cooler outside than inside we open all the doors and windows to start cooling the house back down.

In winter we keep the windows and doors closed all the time and just open the blinds when the sun is shining and close them when it isn’t. But we watch the indoor humidity level closely because this tells us when we need to run our ventilation system in order to reduce humidity and maintain good indoor air quality. In spring and autumn we keep an eye on the temperatures. If the house feels cold and it’s warmer outside, we’ll open it up and vice versa. So you can see that we refer to our weather monitor every day of the year (and many times a day) to help us decide how best to operate the house.

The other screen we constantly refer to is our energy monitor. This tells us when we have excess solar power and helps us decide when to run appliances or do things like plug in our electric car. (Unfortunately the UK company that made the ‘Wattson Meter’ has gone out of business but there are other good options like ‘Efergy‘ and ‘Smappee‘)

The display for our energy monitor sits right above the stove in the kitchen.

The display for our energy monitor sits right above the stove in the kitchen.

So my idea is for a home monitoring system that combines all of the above. In other words it will display the weather forecast plus the current indoor and outdoor temperature/humidity plus the current energy usage and production. This is the vital information that everyone needs in order to be able to operate their home in the most sensible and efficient way possible. In fact I think it should be mandatory for every home to have this information displayed in a prominent location where it can be seen at all times. It might look something like this only attractively designed.

The gadget that every home needs!

The gadget that every home needs!

To further assist homeowners with the efficient running of their house it could be programmed to speak to them and tell them things like, ‘The outdoor temperature just dropped below the indoor temperature, this would be a good time to open up the house and let it cool down’, or ‘Your solar system is making a lot of extra energy right now, this would be a great time to plug in the car’. Of course, in the future this gadget might connect directly to automatic windows and blinds, plus all the appliances in the house, plus the car charger, etc and tell them to operate themselves. But for now it could give helpful advice. It could also be programmed to learn about the particular home and the habits of the residents in order to offer the most useful advice. And now and then it might offer some random piece of wisdom like, ‘Did you know that hanging clothes on the line rather than putting them in the dryer could save you $127 a year?‘. I’m sure you get the idea.

The final benefit of this gadget is that, since it would need to be connected to the internet in order to display the latest weather forecast, it could also send a constant stream of useful data on your home’s energy use/production and the indoor and outdoor climate conditions to a trusted research organisation such as Australia’s CSIRO. If enough homes had this gadget installed it would provide a wealth of information about the way people use their homes, how comfortable they are and how improvements to the home can affect occupant comfort and running costs.

I plan to pitch this idea to the CSIRO as well as to companies that already produce energy monitoring equipment. If anyone reading this has any thoughts about who I should contact or ways I could improve the idea, I’d love to hear from you. Meanwhile, at the very least, get yourself a cheap indoor/outdoor temperature and humidity monitor (I think Bunnings sells them for about twenty bucks) and an energy monitor. I think you’ll find them very useful and helpful.

(p.s. Please note that our strategy of closing the house completely during summer days and opening it up at night works well because our house, and in particular our roof, is very well insulated. In a home with poor ceiling insulation or an unventilated attic it is quite possible that closing the house during the day might cause it to get unbearably hot by late afternoon. Also, different climates require different strategies… what works for us here in the Southern Highlands of NSW might not work at all for someone living in Brisbane for example. You have to figure out how to operate your own house in the best way to suit your climate, your site and your lifestyle. I just hope it involves more than just turning on the air-conditioner.)

Feb 3, 2017: Episode 11 – How To Make a Solar Air Heating Wall

This week we present Episode 11 in our series of short videos about the energy retrofit of the old fibro cottage next to the Greeny Flat. In Episode 10 we explained the reasons why we are turning the whole north wall of the cottage into a Solar Air Heater. In today’s episode we show how.

This completes Stage 1 of the retrofit so we’ll be leaving the videos for the moment and will return with more when we are ready to start on Stage 2.

Energy Performance and Resale Value

In our Newsletter on January 13th I wrote about an excellent website called liveability.com.au which is aiming to move sustainability and energy efficiency into the mainstream of Australian building and  housing development by training real estate agents to recognise and value features like Passive Solar Design and Renewable Energy Systems. In turn, real estate agents will educate home buyers and sellers about the potential for increasing resale value by making energy upgrades to homes that will also reduce running costs and improve occupant comfort.

The beauty of this approach is that, if people can see that it is in their own best interest to make changes to their homes that will reduce running costs, improve comfort and increase resale value, they are much more likely to do those things that also happen to reduce fossil fuel use and greenhouse gas emissions… even if that’s not their intention.

Along those lines I was encouraged this week to see these two articles from the Energy Matters Newsletter that point to solar power and energy efficiency being factors that can improve home values. As noted in the first of the following two articles…

An earlier survey (2014) showed 85% of respondents believed installing solar panels added to a home’s value.’