Blog Archives

March - 'There's never a slow news day for this class!

27/3/2017

There is never a dull moment or slow news day for this class. Some headlines for this month’s reading included ‘The Angry Summer’; ‘Snowy Hydro surge – Turnbull’s plan for $2b expansion’; ‘SA’s state-first plan overturns a decade of power play’; ‘Energy costs eclipse carbon-price levels – Action urged over surge in power prices’; ‘Tesla says its batteries could fix Australia’s energy problems in just 100 days’ and more.

We continue to look out for positive case studies, this month reading about Samso, an island in Denmark which is carbon neutral and runs on renewable energy, with power and profits flowing back into the community

Next month we are heading to Brian Howard’s after our coffee break to see a model built by Brian which demonstrates three different ways of generating power from the sun.

'Chemistry Lesson for Scott Morrison' - Frank Dunin

3/3/2017

A letter to the editor of the Age by Rory McGuire, Pyrmont, NSW was considered by the TSF group not long after a much publicised parliamentary session last year. It intrigued class member and retired CSIRO scientist Frank Dunin, who considers that McGuire even underestimated the benefits silicon and modern solar panels could produce.

Chemistry lesson for Scott Morrison

Treasurer Scott Morrison's display of a lump of coal in Parliament last week could have benefited from more details. Assuming it weighed one kilogram, he could have explained that when burnt in a power station, it would produce two to 2.5 kilowatt hours of electricity, about 2.5 kilograms of carbon dioxide and up to seven grams each of sulphur dioxide and various oxides of nitrogen. It would also produce about 50 grams of fly ash and a few micrograms of heavy metals, including mercury, and some radioactive materials.

Alternatively, if Mr Morrison had displayed one kilo of silicon, he could have explained that it could make about two square metres of solar panels and, at 20 per cent efficiency, with an average five hours of full sun a day, after two days they would have made more electricity than his piece of coal. Then he could have pointed out that modern solar panels are guaranteed for up to 30 years, by which time they would have generated about 2000 kWh of electricity, or about 1000 times as much as his coal lump.

Rory McGuire
Pyrmont, NSW

Here's Frank's response, which he agreed could be published on the website:

'This letter to the editor by Rory McGuire understates the case for solar panels on two counts, assuming his calculations are predicated on solar radiation inputs to Sydney's Observatory Hill with an average daily input of 16.5 MJ/ m2 ( 4.6 kWh). His statement that 2 m2 of solar panels will produce 2.5 kWh from 2 days with full sun for 5 hours is based on the principle of the lowest common denominator.. 2 days each with 5 hours of full sun applies for winter conditions in June/July whereas average daily solar input for any other season will suffice in exceeding a daily power generation of 2.5 kWh.

Long term power generation from the panels over 30 years amounts to 20,000 kWh based on Sydney's average daily input of solar radiation and hence this is equivalent to 10000 times as much as a lump of coal, I suspect a typographical error has crept into the calculation of the superior performance of solar generators over coal.

My overview is still to to congratulate Mr McGuire on a telling chemistry lesson, even if conservative estimates apply.

Frank Dunin
March 3rd, 2017'

Thank you, Frank, for considering this matter further

BSFG on:

'Sustainability'

True sustainability is only achieved when our society achieves this in three spheres of our activity: Social, Economic and Environmental. Sustainability in each of these three spheres is far from being achieved. This has become the concern of governments and ordinary people world-wide and has resulted in many questions about the sustainability of our present lifestyle. This course aims to explore topics such as global warming and climate change, reducing greenhouse gas emissions, clean energy options, the challenge of population growth, sustainable agricultural practices, water use, sustainable use of resources, sustainable and energy efficient building design and various economic and lifestyle issues. Our sessions during the year will examine different aspects of these major topics with a focus on looking towards a sustainable future. No prior knowledge of these topics is required just a general interest in the issues around climate change and sustainability. With discussion of these topics throughout the year you will find that you become better informed about these issues.

Meeting Times

1st and 3rd Friday
10 am to 12 midday
U3A Meeting Room 1

Convenors and contact details

John Lane
0474 936 460

Convenor 2008-2021

John Lloyd

Local Links

Benalla Sustainable Future Group:

Renewable Energy Benalla - website