Tag Archives: climate change

Fun for the whole family with a household waste audit

The waste audit on our path to an zero-emissions home revealed a grand total of 50kg of annual emissions and some ways to reduce it. Here’s how to do a waste audit, and what we found.

Why waste?

The average Australian generates about 1,200 kg of waste each year. The average emissions from municipal (household) waste, is approximately 1.4 times the weight of the waste, meaning that average Australians emit about 1,680 kg of CO2e  each year. Total emissions from Australian solid waste are about 23,000,ooo tonnes per year, or  3.8% of Australia’s total emissions footprint in 2014-5. So emissions from waste are worth worrying about.

Emissions from waste are mainly the result of organic substances, like food scraps and paper, breaking down in landfills. When this happens underground in a landfill, it forms methane, which has about 25 times the global warming potential of carbon dioxide.

Most rubbish bins contain lots of organic waste. Organics are about 65% of household waste when councils do not collect garden and park waste, and about 60% when they do.

My council does collect garden and park waste, but I don’t use the service. Instead I give (nearly) all of my food scraps to the chooks and compost (most of) the rest. We make very good use of the council recycling bin, so our landfill waste is significantly less than would be without that service. So I was expecting my waste emissions to be lower than the average. I did a waste audit to check.

Here’s how to do a waste audit, and what we found.

My household waste audit

Equipment

  • A unit of waste – we used one average week’s waste, collected from all household bins.
  • A tarp, or enclosed area to sort the waste – we used a kids play-pen.
  • A set of scales for weighing the waste.
  • Buckets to hold waste.
  • Tongs, so you don’t have to touch it.
  • Gloves, for the bits you do have to touch.

Method

Decide on your categories.

If you are trying to work out whether the waste is going in the right bins, your categories need to match the bins, eg:

  • landfill waste,
  • recycling,
  • organic.

If you are working on a carbon footprint, then your categories need to match the groups of wastes with different emissions factors, or global warming potentials. This only applies to the organic component and according to the Australian National Greenhouse Accounts Factors (Table 41), includes:

  • food,
  • paper and cardboard,
  • garden and green,
  • wood,
  • textiles,
  • sludge,
  • nappies,
  • rubber and leather, and
  • inert waste.

I was interested both in whether householders were using the right bins, and also in calculating the greenhouse emissions. So I used every relevant organic waste category, plus ‘landfill waste’, which is essentially the waste that should have been in the rubbish bin, because there wasn’t another option. I also added two other categories of interest. They were:

  • paper towels – which I use quite a bit to mop up organic kitchen waste which I don’t want to flush down the sink, as it fills up my septic tank with sludge, and
  • monstrous hybrids – which are an infuriatingly difficult category made up of things that could be recycled, if only they weren’t joined together with things that can’t be.

Sort your waste

Tip the waste into the sorting area, and get to work with the tongs. Put all of the waste into its waste category.

Then, fill a bucket with waste from just one category and weigh it. First you’ll need to zero the scales so that you weight the waste, not the bucket. If you are thinking about bin sizes, you need to estimate the volume, or size of the waste, but for carbon accounting, just the weight will do.

Record the results

Here are the results from my household’s weekly waste audit.

 Category kg
hand towels 0.21
Co-mingled recyclables 0.1
Inert waste 0.58
Monstrous hybrids 0.05
Food 0.19
 Total 1.13

Multiply by 52 to get an annual total.

  Weekly Annually
 Category kg  kg
hand towels 0.21 10.92
Co-mingled recyclables 0.1 5.2
Inert waste 0.58 30.16
Monstrous hybrids 0.05 2.6
Food 0.19 9.88
 Total 1.13 58.76

Calculate the greenhouse gas emissions

To calculate the emissions, you need the emissions factors for each type of waste. These are in table 41 of the Australian National Greenhouse Accounts Factors, which is regularly updated, so get the current version. This gives a multiplier for the weight of each type of waste. To work out emissions, all you have to do is multiply the weight of each organic waste type by the relevant factor, like this.

Weekly Annually Factor Emissions
Category kg kg Multiply by weight kg CO2e
hand towels 0.21 10.9 2.9 31.7
Co-mingled recyclables 0.1 5.2 0 0
Inert waste 0.58 30.2 0 0
Monstrous hybrids 0.05 2.6 0 0
Food 0.19 9.9 1.9 18.78
Total 1.13 58.76   50.44

How did we go?

This gives me a total of just over 50 kg of emissions from waste each year. My household is about 3 people, so that’s only about one per cent of the emissions of an average three-person household (3 x 1680= 5,040).

Frankly, I’m amazed it could be so low, and so I’ll use some other blog posts to look into how I’m keeping it down. Most of it seems to be the chooks, and the aerobic composting, but we’ll see.

Can we improve?

Despite the emissions being so low, there are several things I could do to reduce even further. I could:

  • either stop using hand towel or put it in the council’s green bin. This would take out 31.7kg per year of CO2e emissions.
  • be more rigorous about composting all organic waste or giving it to the chooks. The food waste still in the mix was generally uneaten cat food, or meat bones. These are tough wastes to get rid of, since bones don’t break down, and I don’t like to feed cat food to the chooks, because who knows what’s really in it. However if I could solve this, it would cut out the other 18.8 kg of organic waste. Again, some of it could go in the council green bin.

Why not check your own waste

Inspired? Have a go at doing your own waste audit. Its fun for the whole family. Or perhaps not. As I said in another post, the household 13yo found it totally gross (there were some maggots on the food waste).

Myrle pouring rubbish for waste audit

If you do a waste audit, tell us what you found.

Steps on a carbon-neutral journey

How will I know that my home is carbon neutral? How will others believe me? The first steps are working out what to measure, and how to measure it. This post explains how that’s done.  It’s a little bit dry, so to keep you interested, here’s a snapshot of the next step which was the waste audit, described by the household 13yo as ‘totally gross’.

Myrle pouring rubbish for waste audit

The National Carbon Off-set Standard (NCOS) tells us to do a life cycle analysis (LCA) of the greenhouse gas emissions associated with home. That means working out a ‘cradle to grave’ assessment of all greenhouse gas emissions involved in running a household. The NCOS points us to the International Standard for Environmental Management – Life cycle assessment – Principles and Framework IS014040 identifies four phases for an LCA. Here’s how it looks for my house.

flow diagram for carbon LCA

There are some general standards, and some choices about the scope of a greenhouse gas inventory. These are well established for businesses and products, and they can also be applied to a home. For instance, the Scope 1 emissions from my diagram are really a must. Those are the direct emissions from gas heating and fires, and anything else burned or decomposing at a site. Strangely, human breathing is not included in inventories, even though animal farts may be.

pre-winter solstice bonfire 2015

Emissions from electricity used in a building are also a must in the inventory. But you don’t have to include the full fuel cycle emissions from electricity, like transmission losses from the poles, wires, and the times when high voltage loads are transformed to lower voltages. I’ve chosen to include the full fuel cycle. The interpretation stage gives me a chance to change my mind about this if it’s not working out. Similarly, I’d love to include the emissions associated with the stuff we buy for my home. I would, but the data gathering and calculations are way too complex.

The reason that we can exclude these ‘scope 3’ emissions is that they are all included in the inventories being done by other people or businesses. For instance, I’ll be counting emissions from air travel, even though airlines are required to record and report all of those emissions under Australia’s National Greenhouse and Energy Reporting Scheme.

Keep your eye out for the next post, on my home waste audit. That’s when we’ll start to see how my emissions stack up, and what I can do to reduce them.

Your own pigs don’t stink, or the best way to replace end-of-life power stations with sustainable solutions

By Su Wild-River

Each year the ANU Sustainability Learning Community hosts a Great Green Debate but this year was different. Recognising that there is not debate that climate change is happening, the group instead organised a forum on solutions, bringing together technology and policy experts to discuss sustainable solutions to climate change and energy demands. And what a discussion it was.

The draw-card speaker was Adam Bandt MP, Deputy Leader of the Australian Greens, Federal Member for Melbourne and true inspiration. Adam reflected on a recent trip to Germany and the perplexing differences between Australian and German opinions on wind farms. Wind energy of course is one of the most promising green energy sources and by 2013, new power stations running on wind were about 2/3 the price of new coal – even without the carbon tax.

One of the biggest barriers to wind energy in Australia is Wind Turbine Syndrome, a peculiar condition affecting mainly English speakers who have been exposed to frightening information about wind farms. Adam Bandt believes that Germans are not affected because more than half of the country’s renewable energy infrastructure is owned by its citizens. He talked to a German farmer who confirmed he doesn’t complain about wind farm noise because he owns it, and “your own pigs don’t stink”.

After the trip to Germany, Adam says he spends most of his time wondering how we can increase community ownership of Australia’s renewable energy infrastructure. This is timely because about 40% of Australia’s coal-fired power stations are past their end-life and need to be replaced.

A German presenter gets in the way of the graph that Adam Bandt MP intended to photograph. Adam is the small, dark pointer at the front of the slide.

A German presenter gets in the way of the graph that Adam Bandt MP intended to photograph. Adam is the small, dark pointer at the front of the slide.

Windlab is well on the way to providing a solution to Adam’s dilemma. Garth Heron spoke about the Coonooer Bridge wind farm in Victoria, which is the first renewable energy project in the country with an ownership structure that includes the local farming community together with the developer. Garth also showed off Windlab’s wind prospecting technology and energy models showing the feasibility of electricity co-generation from solar and wind. In some places, the wind and sun can reliably generate baseload energy throughout most of every day, with more energy produced than is needed for many hours.

The bright future for renewable energy harvest went pocket-sized in Professor Hoe Tan’s presentation on nanotechnology solutions. He’s harvesting solar energy using photonic devices about the size of atoms and integrating them into bigger applications, hugely increasing the amount of electricity that can be generated.

With enough renewable energy capacity in the bag, the climate solution discussion shifts to battery technology. Professor Christine Charles is developing hydrogen fuel cells that could soon install rocket power into clean, green cars, as well as stationery settings.

Many commercial property developers are actively progressing the green energy agenda. James Bichard, the Development Manager at the Molonglo Group which designed the Nishi Building in New Acton explained how energy efficiency is fundamental to the design of their new, iconic cinema/office/apartment block which won the International Project of the Year at the 2015 Building Awards in London . Green energy doesn’t have to be elite either, with Nishi holding a proportion of it’s apartments at an affordable entry level for new home-owners.

Of course all of this needs financial support and the Clean Energy Finance Corporation has the solution. This profitable government body secures financing solutions for the clean energy sector. The CEFC partners with commercial financiers and focuses on projects and technologies at the later stages of development which have a positive expected rate of return and have the capacity to service and repay capital. The CEFC’s 2013-14 Annual Report revealed a total project value of $3.2b, and a positive return of $2.40 profit for every dollar it invests.

Compact or large-scale combined solar and wind power generation, efficient battery storage, green buildings and the CEFC are quite possibly the best way to replace end-of-life power stations with sustainable solutions. These are all proven, cost-effective and available now. In light of these options it seems inexcusable for Australia’s Coalition government to threaten Australia’s Renewable Energy Target and its associated research, development and financial initiatives as they are this week in Australia.

Thanks Alexander Ferguson, Karen Hussey and the Sustainability Learning Community for these amazing stories to support our outrage. 

In Search of the Climate Change Monster

Climate Change Monster

The Climate Change Monster Image Credit: Artwork by Thomas Bonin, http://www.tombonin.blogspot.com

By Su Wild-River

This article was first published in No Funny Business on 18/10/2013.

If you are a climate obsessive like me, you spend a lot of time reading the science, watching the weather and taking action on climate change mitigation and adaption. Each new off the chart heatwave, warmest winter on record and extreme flooding event just reinforces the message that we are already feeling the personal effects of climate change. So why is the world backing offon action?

According to Cass R. Sunstein, the barriers are partlypsychological. Action would be easier if climate change caused a recent and repeatable crisis, had a clear and hateable perpetrator and posed an immediate threat. Extreme weather events have some of these features, but by definition, climate change doesn’t. It’s the bigger, slower trend surrounding and influencing weather, exacerbating the extremes, but never fully explaining them. The USA came up with Frankenstorm to help mobilise action on Hurricane Sandy. Does Australia need to name its weather demons to gain more traction against the Climate Change Monster?

The Climate Commission named Australia’s record-breaking heatwave of 2013 the “Angry Summer”. This weather demon attacked me directly – although I got off more lightly than others. I spent the catastrophic fire danger day cleaning up my rural property, spraying water on the chickens, and watching as the smoke from a bushfire 100km away came quickly closer before being halted by fire fighters and a creek. But even dangerous weather demons have several faces, and for many, the Angry Summer was a great day at the beach.

Weather demons like the Angry Summer are a powerful drawcard for science communication. Every time there’s an extreme weather event, the Bureau of Meteorology’s website is snowed under. In 2010-11 the BoM received 3 billion hits for its 30,000 warnings and 140,000 forecasts. The Climate Commission also has great graphics and regular updates, but while ‘weather deniers’ are unheard of ‘climate denial’ is still a most popular Australian spectator sport.

I was touched by the Climate Change Monster in 2014. The hateable perpetrator was the tiny, invisible Irukandji Jellyfish, perhaps the most venomous creature in the world. A fluther of these monsters were nearly 1000km outside of their normal rangewhen they stung and killed two friends of mine at Ningaloo Reef. The repeatability of the event and its potential threat is evident when I see elegant tropical fish while snorkeling in ‘temperate’ waters. It seems likely that the presence of Irikandji where they weren’t expected was due to the Very Much Above Average ocean temperatures in Australian oceans. But even though this event was more ‘climate’ than ‘weather’, climate change was not mentioned in the news reports on the tragedy.

The scientific consensus tells us that climate change is real and growing ever more dangerous. Scientific knowledge is essential for understanding and tackling climate change. But if we are psychologically hardwired to not see the climate for the weather, then solving this global crisis will take more than science. We need to find new and creative ways to focus public attention on climate change.

My Climate Change Monster is a giant, invisible and many-tentacled Climate Change Monster that creeps slowly then suddenly spits out deadly weather and venomous pestilence. How does the Climate Change Monster appear to you?