Low-energy homes don’t just save money, they improve lives

Eco-houses at Scotland’s Housing Expo, Inverness. What is it like to live in a house like this?
via Wikipedia, CC BY-SA

Stephen Berry, University of South Australia; David Michael Whaley, University of South Australia, and Trivess Moore, RMIT University

Household energy use is a significant contributor to global carbon emissions. International policy is firmly moving towards technology-rich, low- and near-zero-energy homes. That is, buildings designed to reduce the need for additional heating, cooling and lighting. They use efficient or renewable energy technology to reduce the remaining energy use.

But what about the experiences of people who live in homes of this standard? Are these homes comfortable, easy to operate, and affordable? Do people feel confident using so-called smart energy technology designed for low energy use? What support systems do we need to help people live in low-energy, low-carbon houses?

We worked with other Australian and UK researchers to understand what it’s like to live in purpose-built low-energy housing. As part of this project, researchers from Sheffield Hallam University and the University of Salford in the UK visited South Australia to collect data from Lochiel Park Green Village, one of the world’s most valuable living laboratories of near-zero energy homes.

Lochiel Park’s 103 homes were built in the mid-2000s to achieve a minimum of 7.5 energy efficiency stars. They’re purpose-built to be a comfortable temperature year-round, and are packed with a solar photovoltaic system, solar hot water, a live feedback display to show households their energy use, plus a range of water- and energy-efficient appliances and equipment. Combined, these systems reduce both annual and peak energy demand, and supply much of that energy at a net zero-carbon impact.

To reciprocate, we spent several weeks investigating similar examples of niche low-energy housing developments in the Midlands and the North of England. We listened to the stories of people living in low energy homes, who experience the difference on a daily basis, and from season to season. They help us look beyond the dollars saved or percentage of emissions reduced; for them the impact of low-energy homes is personal.

This research provides new insights into the relationship between people, energy technologies and low-carbon buildings. For example, one elderly householder told us that moving into a dry and warm low-energy home allowed their grandchildren to come and stay, completely changing their life, and the life of their family.

Low-energy homes create a wide range of physical and mental changes. Several households spoke about health improvements from higher indoor air quality. Even the idea of living in a healthier and more environmentally sustainable home can prompt lifestyle changes – one woman in her mid-50s told us she gave up smoking after moving into her low-energy house because she felt her behaviour should match the building’s environmental design. She also shortened the length of her showers, reduced her food wastage, and lowered her transport use by visiting the supermarket less often.

Purpose-built low-energy homes also give economic empowerment to low-income households. One household told us that savings on energy bills let them afford annual family holidays, even overseas. This economic benefit matches our findings in other Australian examples.

As researchers, we might dismiss this as a macro-economic rebound effect, voiding many of the energy and environmental benefits. But to that household the result was a closer and stronger family unit, able to make the types of choices available to others in their community. The benefits in mental and physical wellbeing are real, and more important to that family than net carbon emission reductions.

Although international policy is firmly moving towards technology-rich, low-energy homes, our research shows that not all technology is user-friendly or easy to understand. For example, some households were frustrated by not knowing if their solar hot water system was efficiently using free solar energy, or just relying on gas or electric boosting. Design improvements with better user feedback will be critically important if we are to meet people’s real needs.

This research highlights the importance, in the transition to low-energy and low-carbon homes, of not forgetting the people themselves. Improving real quality of life should be the central focus of carbon-reducing housing policies.

Stephen Berry, Research fellow, University of South Australia; David Michael Whaley, Research Fellow in Sustainable Energy and Electrical Engineering, University of South Australia, and Trivess Moore, Research Fellow, RMIT University

This article was originally published on The Conversation. Read the original article.

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Getting rid of plastic bags: a windfall for supermarkets but it won’t do much for the environment

Gary Mortimer, Queensland University of Technology

Moves by major supermarkets to stop providing free plastic bags could earn these businesses more than A$1 million a year, but may only have a small impact on the environment.

Australia’s two supermarket giants, Woolworths and Coles, have announced that their stores will stop offering their regular plastic bags within 12 months. Instead, customers will be able to buy a more durable plastic bag at 15 cents apiece, or simply bring their own.

These bags are factored into the cost of doing business for these supermarkets. There are costs beyond just the bags themselves, such as the costs associated with sourcing and negotiating with packaging suppliers, procuring them, shipping and warehousing them, and distributing them to stores only to then give them away.

Supermarket margins are already feeling the strain of price deflation. These businesses are generally making less than 6c in the dollar, so the opportunity to phase out this cost certainly makes good business sense. The table below provides an estimate of current costs.

Estimated current costs

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While retailers stand to pocket this saving, the switch to stronger, multi-use plastic bag brings with it its own costs. To begin with, the bags alone cost more (9c each) and also have associated procurement costs.

However, the new scheme will immediately reduce customers’ bag usage. Being optimistic, it would be reasonable to see an 80% decline in plastic bag use as shoppers actively search for alternatives to free bags.

Most shoppers will probably reuse the 15c bag, or look to other options like canvas bags, polyethylene bags or cardboard boxes. In turn, while the new re-usable bag may cost more than the thinner single-use bag, fewer will be used and therefore ordered. Retailers can expect to see a reduction in these packaging costs.

Estimated costs under new scheme

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It’s estimated that Australian retailers give away 6 billion plastic bags each year. Woolworths alone say they provide 3.2 billion each year. Coles has not provided an estimate of bag use, but claim to process 21 million transactions each week. With fewer stores than Woolworths, I estimate that Coles may give away up to 2.7 billion bags annually.

With each bag costing almost 3c, retailers stand to save more than A$170 million a year in direct costs. Selling these new bags at 15c each effectively creates another revenue stream potentially adding up to A$71 million in gross profit (6c x 1.18 billion units).

It might not actually reduce bags

In 2013, Target reverted back to providing free plastic bags after three years of charging 10c per bag. Other than hardware retailer Bunnings, no other large retailer has initiated a voluntary ban on single-use plastic bags.

Some Australian state and federal governments have been pushing for single-use plastic bag ban for almost 10 years. South Australia was the first to ban plastic bags from supermarkets in 2009, followed by the ACT in 2010, Northern Territory in 2011 and Tasmania in 2012.

In 2016 the Queensland Government released a discussion paper on the proposed ban. It is predicted all states will fall into line by mid-2018.

The past impact of applying a charge to the use of plastic bags has provided positive, but mixed results. In Australia, Bunnings reported an 80% reduction after implementing a charge for plastic bags, while a 2008 trial undertaken in three Victorian regional towns by Coles, Woolworths and IGA resulted in a 79% reduction.

In 2002, Ireland applied a 15 pence (22c) charge to single-use plastic bags, claiming a 90% reduction within 6 months (this was before the transition to the euro currency in the same year). Then in 2007 it increased the charge to 22 euro cents (32c) in response to increased bag usage. Sadly, shoppers had become conditioned to the 15p charge and returned to their old habits.

The UK government likewise reported an 85% reduction in single-use plastic bags in the first 6 months after a 5p charge (8c) was implemented in 2015. Similar results have been reported in the US, with a 94% reduction in Los Angeles County from the introduction of a charge for bags.

In the above cases (excluding Australian examples), single-use bags were still available, however a levy was applied, creating revenue for governments to channel back into environmental programs. This model is not the planned approach for Australia, were all single-use bags will be replaced with either the heavy duty (>35 micron, LDPE) option at 15c or the “green” polyethylene bag.

Charging for bags has minimal impact on the environment

Unfortunately, introducing a charge for bags doesn’t help the environment in isolation. While plastic bags represent only about 2% of landfill, there is certainly sufficient scientific evidence that plastic bags do present risks to marine life and clog waterways.

However, simply charging for a plastic bag, without directing these funds into environmental programs, does not necessarily resolve the problem. Shoppers slowly return to old habits, governments and retailers stop educating consumers and re-usable bags soon make their way into water ways and landfill.

Some shoppers simply forget to bring re-usable bags with them. The UK Department for Environment, Food and Rural Affairs found that the average UK household had 40 plastic bags stashed away around the home. Also a South Australian parliamentary review found that only about 30% of shoppers actually recycled their re-usable bags.

In the US, studies indicated 40% of shoppers continued to use disposable bags, despite a 5 cent levy.
Moving to a reusable option also doesn’t stop people discarding these new bags either. Another US study found many people still threw away reusable bags.

Ultimately, “banning the bag” is only the beginning. Retailers will need to remedy customer complaints as the phasing out of plastic bags begins.

Like UK retailers, Australian supermarkets could choose to funnel some of the profits derived from the 15c reusable bag into community programs or environmental groups. Australian governments will also need fund ongoing education campaigns to draw attention to bans, alternatives and outcomes.

Gary Mortimer, Associate Professor, Queensland University of Technology

This article was originally published on The Conversation. Read the original article.