Home Energy Analysis

A couple of posts ago, I bemoaned an apparent lack of interest from Australia in the Solar Decathalon, a competition challenging home builders. Australia does have the World Solar Challenge which requires cars to travel 3000 kilometres North-South across Australia powered entirely by the sun. There have been nine races since the first in 1987. Average speed then was 67 km/h but this year’s winner averaged 91 km/h and was restricted by road and other rules from achieving a higher speed.

Each year the rules become tougher as technology improves. For instance solar collector area was 25% less in 2007 than in 2005 and drivers were required to sit upright lessening the aerodynamic efficiency of a prone driver. Teams are mainly from universities. For the fourth consecutive year, a team from the Delft University of Technology (Netherlands) produced the winning car.

We won’t ever be seeing any of these mobile laboratories disguised as cars  in car showrooms for sale, but high end technologies have a way of percolating down. (Can you imagine the 2012 Formula 1 series requiring cars to be electric and fuel cell powered?)  The team members involved will be taking their knowledge and enthusiasm into diverse industries.

Yesterday I went to work a little early, and because it was the first Monday in November traffic was light. (For those who don’t know, the Melbourne Cup is run on the first Tuesday in November, and it is a public holiday. Many workers give themselves a four day weekend by taking Monday on Annual Leave. Hence, little traffic.) In the couple of months since I have been driving our “new” car to work, I’ve played a game of minimising fuel consumption, keeping score by watching the car’s computer. Yesterday was a record.

This made me think of the role that analysis of performance plays in my life. One area is that each year I run the Melbourne Marathon, and every year I recognise that training must commence immediately if I want to run an acceptable time. When I start training, distances are short, times are slow. Nothing is written down. When fitness increases, I start recording training in a diary - now Excel but originally a paper diary. The fitter I get, the more detail and analysis goes into the spreadsheet which becomes a motivator - “I can’t miss training today, because the 7 day rolling average would drop.” A couple of years ago, my training was so bad that no diary survives. In a slightly different class, Robert de Castella went over 1000 days in a row where he ran at least twice.

I assume the Weight Watchers organisation uses the weekly weighings for a similar reason. Those participants who succeed will do so at least in part because of seeing the achievement of weekly successes, each of which will be small, but the cumulative effect can be the desired weight reduction.

Here comes the commercial. The Home Energy Analysis System can operate in the same way by enabling monitoring of energy consumption and carbon dioxide emissions. The graphs available will soon show changes by day, week or month. Stick them on the refrigerator so that the whole family can see what is happening.

The 2007 Solar Decathalon was recently held in Washington D.C.: twenty teams from colleges and universities designed and constructed solar powered houses. Groups from all over the world applied, and 20 were selected to submit their houses with the help of $100,000 from the Department of Energy. The selected teams were mainly from the US, but there were two teams from Europe, and one each from Canada and Puerto Rico.

The houses were to be completely independent from the power grid, to the extent that one of the requirements was to use energy generated from the home to power commercially available cars. Photovoltaic cells were used to generate power, although one house also had three windgenerators. All had solar driven water and space heating systems.

There were ten contests from which the teams could gain points. “Architecture” provided most points and livability contests of various kinds featured highly. Engineering was just one of the contests so that the houses are more than a technical solution to the problem. It is true, however, that many of these homes would stand out in Melbourne streets and might have some difficulty gaining planning approval. 

Visitors were able to view the homes during the competition period and apparently interest was high with long queues.

The winning entry was from Technische Universität Darmstadt Germany. Bosch appliances were used extensively. Sponsorship in kind and money was important to all entrants as $100,000 represents a small part of the cost of development and construction, typically over two years. Photos indicate that the German team had more than 30 student and faculty members which I assume is typical of team size.

 The next contest is in 2009 and I hope that some Australian institutions are quietly preparing their entries. I will donate a copy of the Home Energy Analysis System!

Thanks to this blog post we are now the proud owners of an electricity consumption meter. This enables me to wander around the house to measure the wastage associated with devices left on stand-by. So far, my conclusion is that there is more to be gained by switching off lights in vacant rooms and ensuring that the 450 watts of back yard lighting is on only when necessary. We had a renovation a few years ago, and our architect who was “good with lighting” left us with a large number of quartz halogens. At that time, we were lead to believe they were energy efficient. We only replace blown globes if they happen to be in a critical area.

Even the power board in my son’s room which feeds screens, playstations and assorted other things that glow, draws less than 20 watts. He should still turn it off. 

The laser printer, left on for the last 18 months just in case it was needed, was drawing about 15 watts. The inkjet that superseded it draws zero according to the meter and reached a maximum of 17 watts when printing. This report found an average of 3.4 watts for inkjets which is the consumption that Epson claims for sleep mode. Perhaps it is a power factor effect.

The worst appliance found so far is the tumble dryer which draws 1800 watts when in operation. Not only that, it shrinks all my socks. 

This morning the good people at Yarra Valley Water sent Keith and Nash(sp?) to our house as part of a program to audit and survey water use. They had a look at flow rates from our taps and showers. They asked how often we flushed our toilets. We are partial believers in “If it’s yellow, let it mellow, if it’s brown, flush it down”, but our answer was an estimate with a large error potential. The toilets are new, and dual flush with a relatively modest volume so we are efficient on that score.

We received a printed report with a number of suggestions:

• install more efficient shower heads - estimated saving of 23,926 litres per year
• persuade our teenage son to have shorter showers
• install flow control valves and aerators on taps 

They gave us a $40 voucher to one of Melbourne’s larger stores and I gave them a copy of one of the reports from HEAS  which is the least I could do.

I’ve always thought bottled water a waste of resources and some recent reading supports this belief:

• It is expensive to buy at approximately $2.00 per 600 ml. Petrol was less than $1.20 a litre this morning (not tonight, but that’s another story). Piped to our home, water costs less than a dollar per 1000 litres here in Melbourne.
• The production of bottles uses considerable crude oil.
• The bottles are recycled less than most other containers, at least in part because bottled water is often consumed outside the home.
• There are considerable transport costs in bringing Evian water from the French Alps or Fiji water across the Pacific Ocean.
• The crude oil equivalent of bringing bottled water to market, when everything is taken into account, is 20% of the bottle’s volume.

On a not completely unrelated topic, apparently the Japanese have been able to buy diet water for three years. I can’t wait until it’s available here.

The non-Australian reader might need to consult an atlas to see that Tasmania and Victoria are some distance apart and that there is a considerable amount of sea water between them. Nevertheless, there is a suggestion that Victoria’s water crisis could be lessened by piping water from Lake Margaret in North West Tasmania to Victoria.  No pumping would be necessary as the Lake is 600 metres above sea-level. Apparently the 350 kilometre underwater section would be easily built by comparison with other projects, for instance,  a gas pipeline being constructed between Norway and Britain.

Lake Margaret is the site of Tasmania’s first hydro electricity centre, beginning production in 1914. The area has reliable rain, apparently receiving 177 inches in 1948. Melbourne, by contrast, receives an average of 24 inches (600mm). There would be some negative effects on the environment by such a large infrastructure project. Tasmania is used to robust discussion of major projects.

 The desalination plant planned to be built in Victoria over the next few years has obvious environmental impacts and with considerable ongoing electricity use and carbon dioxide emissions.

By comparison, a pipeline would be almost benign. As it is claimed it could be operational more quickly and cheaply than a desalination plant, it seems to be well worth further investigation by our elected representatives. 

Most of us are familiar with the term “Peak Oil”: the idea that oil production will at some stage decline if it hasn’t already happened. Similarly, Uranium is estimated to last for 80 years at current usage rates. Consumption will accelerate as nuclear power is inceasingly used for power generation, but exploration is likely to increase reserves.

A recent article in New Scientist (David Cohen, “Earth Audit”, May 26) listed some lesser known minerals which will be depleted in the near future. Hafnium, which has some use in photo-voltaic technology, has approximately 20 years of known reserves at current usage rates. Indium is also used in PV technology and LCD screens and could be exhausted earlier. The list goes on, but the message is that even emerging technologies will potentially have difficulties with raw materials.

It would be a tough form of justice if we humans still had some oil when the materials enabling now emerging technologies have gone.