Indholdsfortegnelse for 170 / Jan-Mar 2025 i Renew Magazine

You would be hard pressed to drive down any Australian suburban street and not see at least several rooftop solar energy systems. Australians have embraced rooftop solar with gusto, and that’s no surprise given that we have some of the cheapest rooftop solar systems on the planet (for example, typical costs in the US are around three times what we pay!). With a suitably sized solar system, it’s possible to offset virtually all your electricity consumption—indeed, many Renew readers have reduced their electricity bills to almost nothing, or even run in credit. So, it should come as no surprise that Australia recently passed a new milestone—there are now over four million domestic rooftop solar installations in the country, which is around one system for every three detached dwellings. Compare that…

* with thanks to Rob Law for his previous work on the report: Minimum energy standards for Victorian renters: an analysis (2024). While owning your own home is perceived in Australia as the ‘preferred option’, the number of households renting is trending upwards, from 27% two decades ago to 31% in 2021.1 And in the corresponding period, housing costs (adjusted for inflation) have increased by 50% for private renters.2 The cost of renting, combined with the poor availability of rental properties, particularly in some locations, means that more often, those looking to rent have less choice and face increased competition. When looking for a place to live under time pressure, many renters might accept what’s available rather than hold out for something better. Finding a home that will be warm…

I had long wanted to add a solar hot water system (HWS) to complement the solar PV I installed 10 years ago to further reduce my carbon footprint. I found a second-hand, 10-year-old, operational Solahart 315L system for $500 online, which I learned was being replaced due to a hail damage claim on the corrugated iron roof beneath it. My roof is almost flat, where originally the solar HWS was mounted on a 20-degree pitched roof. I was pretty sure it needed to be inclined but was assured by the plumber that “it’ll be right”. It wasn’t. When I complained of the lack of performance (having done lots of research online), he agreed an inclination frame would improve this, but pointed out it was my job to source one. After…

Almost half the world experienced extreme drought in 2023 New global findings in the 8th annual indicator report of the Lancet Countdown on Health and Climate Change reveal that people in every country face recordbreaking threats to health and survival from the rapidly changing climate, with 10 of 15 indicators tracking health threats reaching concerning new records. In 2023, people were exposed to, on average, an unprecedented 50 more days of health-threatening temperatures than expected without climate change. Extreme drought affected 48% of the global land area—the second-highest level recorded—and the higher frequency of heatwaves and droughts was associated with 151 million more people experiencing moderate or severe food insecurity than annually between 1981 and 2010. The report calls for the trillions of dollars spent funding fossil fuels to be…

After finally realising that hydrogen is a transport dead end, iron ore mining company Fortescue Metals has decided to go all-in on moving to battery electric machines of all sorts. Recently, Fortescue cancelled their plans for green hydrogen and ammonia production at the Middle Arm precinct in the Northern Territory as well as cancelling plans to work with energy company AGL on a green hydrogen plant at the Liddell site in NSW. Instead, Fortescue has committed to a US$2.8 billion deal with Liebherr Group for the supply of battery electric mining machines, included 360 autonomous battery electric haul trucks, 55 electric excavators and 60 battery electric dozers. Fortescue has plans to profitably eliminate greenhouse emissions from mining by 2030 by eliminating the need for diesel machinery and gas. Fortescue head…

Women’s Environmental Leadership Australia is a fast-growing community of women and gender-diverse changemakers transforming Australia’s response to our environmental and climate crises. Through leadership programs, WELA helps participants find their voice, build confidence and step into impactful roles. It also funds women- and gender-diverse-led projects and champions gender-aware approaches to ensure that diverse voices are amplified where they’re needed most. Renew: How does gender intersect with the climate movement, and why is it important to train women and gender-diverse people in environmental leadership? Victoria McKenzie-McHarg: Gender intersects deeply with the climate movement. Structural inequalities like patriarchy, colonialism and capitalism mean that women and gender-diverse people often feel the impacts of climate change the hardest. For example, 80% of people displaced by extreme weather globally are women. At the same time, these…

Food waste collection services have dominated the discussion around waste management and landfill emissions recently. Centralised, government-steered, kerbside-collected waste management has for around a century been the number one strategy and expectation for almost all streams of household rubbish, but as we know from the renewable energy sector, a centralised service is not always best in every situation, and won’t always cover the whole population. As with other infrastructure services, we have the option to manage organic waste on a second level, in the household, but also on a third, in the community. Centralised services have made things convenient over the last century: out of view, implemented via industrial operators through government contracts, with costs that are withdrawn from us in a vague bundle of periodic rates. With a background…

Omnipresent as it is, the potato takes quite a complex journey from genesis to our plates. It’s also a journey that’s become more sustainable and innovative as the decades have gone by. As home gardeners will know, potatoes are produced clonally—meaning they are grown from tuber seeds rather than botanical seeds. This makes potatoes more susceptible to disease than crops such as wheat that are grown from seed, as the potato’s genetic materials are transferred from one generation to another. And the more potatoes that are lost to disease, the more crops and resources are wasted. This is where Nigel Crump and his team at AuSPICA come in. Based at the Toolangi Research Station—a 52-hectare farm north of Melbourne—AuSPICA is a not-for-profit that produces minitubers for Australian potato growers. AuSPICA…

There are a number of problems that contribute to what has been described as the housing crisis in Australia, and that result in many people being homeless, including a lack of homes to meet demand, and a lack of affordable housing options, which makes homes well beyond the budget of many. Decreases in family sizes means that more homes are needed to house the same number of people than a few decades ago. There is not enough existing housing stock or new housing being built to meet those requirements, and much of what is being built are large, and often expensive, homes, which means many people simply cannot afford to live in the city or suburbs in which they wish to for family or work purposes. With the average house…

Now that the national fuel efficiency standard has commenced in January 2025, we can expect to see some shifts in the vehicles on sale in Australia to include models of battery electric vehicles (BEVs) and plug-in hybrid vehicles (PHEVs) that have been on sale in overseas markets for years. As BEV sales have taken off, PHEVs and traditional hybrid vehicles are now being marketed with enthusiasm. PHEVs are combustion engine vehicles with a medium-sized battery that can be plugged into the mains to give a certain amount of electric operation. These contrast with traditional hybrid vehicles, which can’t be plugged in and their small battery can only be charged by recovering energy when slowing down or directly from the internal combustion engine, giving modest fuel savings. Some describe PHEVs as…

Helsinki, Finland’s capital, which has set a target of becoming greenhouse neutral by 2030, uses large district heating systems to warm the homes of residents. District heating systems use megawatt-scale heat sources to heat vast volumes of water, piping that hot water to homes for use in hydronic heating in each home. However, many of these heating systems have traditionally used gas or even wood to heat the water, with the associated greenhouse emissions and pollution. Finnish energy company Helen Oy has commissioned MAN Energy Solutions to supply an air-to-water heat pump as part of its Patola heating plant complex in Helsinki. The new heating plant will include a massive heat pump which will be the world’s largest air-to-water heat pump, with a rated output of 33 megawatts—compare that to…

You might have seen the graph opposite from a recent paper from Heather Mirletz and colleagues, published in Nature Physics.1 It has been shared a lot in my circles on social media. The authors estimate that solar waste in 2050 will be very small compared to other waste flows. Between 2016 and 2050, solar waste generation would amount to 54 to 160 million tonnes: less than one-tenth of e-waste streams, and at least 99.6% less than coal ash and municipal waste. This is important context given mounting fears about huge quantities of dumped panels. This work was focused on solar, but other studies have looked at projections for wind power. A study by Pu Liu and Clare Barlow estimated that global cumulative turbine waste by 2050 would be around 42…

Living off grid with an electric vehicle for over five years has given me a good understanding of how best to use solar energy for charging. The first thing to realise is that charging an EV from your off-grid home using solar array is very doable. What I have found even more astounding is the incredible efficiency of transferring the energy of sunlight to EV wheel rotation, considering the outputs of commercial solar farms. Some solar farms have array areas expanding hundreds of hectares, such as one proposed by BNRG Renewables Leeson near Bairnsdale in East Gippsland (176Ha). If we consider the energy output of just one hectare (that being 100m by 100m), the kilowatthours of energy generated in one year can be expressed in its capacity to drive an…

Depending on who you listen to, the self-driving (autonomous) car is either just around the corner or unlikely to be seen in our lifetime. Whilst the reality is probably somewhere in between, the media hype of late would give the impression that it is more ‘sooner’ than ‘later’. But is that really the case? To start with, self-driving vehicles have been theorised and experimented with for longer than many people realise. For instance, Bel Geddes in his 1940 book Magic Highways suggested they would be reality by the 1960s! Early experiments through the 1940s and ’50s were reliant on wires and signals embedded in the road. Unfortunately for these, traffic in the form of pedestrians and other non-connected moving (or even unexpectedly stationary) items provided an insurmountable issue. Camera vision-guided…

Have you been off-grid long? Just over 60 years now. We couldn’t afford it when the grid came through in the 1960s. And dad refused to clear a wide, nearly one kilometre long swathe through the on-farm two square kilometre forest for the power line. I’m also disinclined to wreak such havoc, especially given our climate future. Thankfully, the days of kerosene lanterns and candles are well behind us, and the thunderbox dunny isn’t missed either. Having to light a fire in the cast-iron stove, to make hot porridge before a dawn departure by car to the school bus-stop, was done by lamplight on stygian winter mornings, but having kindling prepared meant we could avoid having to go out into the frost in the dark. Recent decades with a 3kW…