Energy & Efficiency

Energy underpins every action and is so fundamental to our modern way of life that we don't even pause to consider how reliant we are on affordable, reliable concentrated flows of energy. We take pride in doing as much as we can with renewable energy, usually in the form of human muscle power derived from sunlight via plants. 

What would you do when fuel becomes more expensive or temporarily unavailable? How will you manage a prolonged power outage during winter?

Having backups and redundancy is one way to mitigate the disruption and discomfort. What does this look like for you? Grow some firewood, store candles, insulate, consider solar powered solutions.

Pumping with free energy

Pumping with free energy

Using water to pump water, now that is cool! I have been building a small ram pump for lifting water. The design uses off the shelf components assembled and then cast in concrete.

Overview: Water from a small creek enters a screened intake and is carried via 32mm polythene piping. This has a drop of perhaps a meter over about 70 - 80 meters. This connects to 18 meters of rigid steel 25mm pipe which drops a further 10 meters to the pumping unit. The outlet from the pump delivers water via 15mm poly tubing up to an elevation of around 30 - 40 meters.

While the device works technically it has a number of drawbacks:
  • The water delivery is very slow, perhaps 1 litre every 2 - 3 minutes. This is a result of the various measurements. More water in, dropped from higher or delivered lower would improve the situation.
  • The pump unit stops every day or so due to (I believe) air accumulating at key points in the delivery line. This can be improved by eliminating high points from the line.
  • Pump stops when river drops too low
  energy  water  technology 
Electric lawnmower upgrade

Electric lawnmower upgrade

After trying various different 'eco' lawn mowing solutions we were struggling to find something that could live up to our expectations. Our latest attempt is so far proving quite satisfactory, despite my misgivings about battery powered tools capability to deliver enough power. Introducing the STIHL RMA 410C A quiet, exhaust free way of keeping the paths under control.December 01, 2016  lawn  electric  technology 
The brazier

The brazier

Details  Both a focal point for outdoor gathering and warmth with perhaps the option for grilling, frying, toasting etc. Constructed from welded metal fencing standards held within a circular 'collar' made from the cut down wheel of an old sheep shearing machine. Located at the focal point of the outdoor spiral.Date  September 04, 2016Tags    fire 
Solar - third time lucky

Solar - third time lucky

After several failed attempts to create a low cost, low tech solar water heater I gave in and purchased a complete kit off the shelf. It's only August but we've been having some nice fine days and the temperature has been getting up to high 50's. This unit has 20 evacuated glass tubes with some kind of antifreeze that exchanges heat with water that is pumped through the header. While I would have preferred a passive system I do like the modular nature and programmable smarts of the control centre.August 21, 2013  solar  energy  water  technology 

Energy efficiency with hot water

Currently most of out hot water heating is done by electricity although we are are working on a number of strategies to reduce this component. One part of the approach is to keep the thermostat set so that the water is just hot enough.

I was having a conversation with someone about energy efficiency and hot water heating and what was the best temperature setting for the hot water cylinder.

The friend was operating under the incorrect assumption that it was better to have the cylinder as hot as possible so that when water was taken out, for a shower say, there was less cold water entering that required heating. There is a certain surface logic to this but it seemed to me that it doesn't matter what temperature the water is, when you have a shower or do the dishes you are extracting the same amount of energy (in the form of hot water) from the tank and so the energy needing to be replaced is the same.

The issue with keeping water extra hot then, is more to do with the extra energy that is required to maintain a greater temperature  differential between the temperature inside and outside the hot water tank.

According to one website:
"The ideal setting is 60°C. It is important that the water in the cylinder is this hot to kill bacteria such as legionella but higher temperature settings only increase your power bill."
June 17, 2011  energy  hot water  electric  temperature  efficiency 
Energy efficient bulbs

Energy efficient bulbs

I recently purchased a couple of compound LED light bulbs. These use an extremely low level of power (11 Watts each) while providing a useful illumination.

Available in either Edison thread or bayonet they fit into a standard light socket. Being LED they do not contain any mercury.

Unfortunately I have already had one cut out for some reason.
http://www.eoutlet.co.nz/catalog/viribr... June 10, 2011  LED  Light  Energy 
Measuring the sun

Measuring the sun

As part of my ambition to get a solar electric system up and running I have been conducting some tests.

My interest is in the effect of the suns angle to the panel array and the relationship to voltage. While there are probably some models put there, I have not seen any and find that actual experience is much more convincing and reliable.

My observations will influence my decision to include tracking capabilities to my solar installation.

Notice the clever little rod below the panels whose shadow (or lack of) can be used to determine if it is pointed directly at the sun.
May 18, 2011  solar  electric  measure  photovoltaics 
Spinning with the wind

Spinning with the wind

Experimenting with vertical axis wind energy harvesting mechanisms.
Using old bicycle wheels and pieces of fat pipe I managed to put together a trial device for collection energy from the wind. Determining the angle of the 'blades' is the important factor. The next version will be bigger and better and allow for fine tuning.
January 13, 2011  wind  energy  VAWT