Wednesday, 27 June 2012

up up and away ...

Well I got a notice in the mail today from the power company letting me know that both parts of my power bill are going up. That would be the 'regular supply' and my 'off peak' (Tariff 33)

What is most interesting however is that the off peak power is raising to such an amount as to be unattractive. Clearly they want to drive people away from 'off peak'
Which is interesting as I'd say that the majority of off peak setups on this here in Queensland will be hot water systems.
I can only guess that the extra 'feed into the grid' of rooftop solar (no its not stored) has meant that peak management is harder now (either that or its a money grab)
I've plotted the ratio of the prices on this graph to make that clearer, but where it was earlier nearly half price for off peak power (and on Tarrif 33 the energy supplier decides even when you get that energy), it is now only about 25% cheaper than regular power which I can use as I choose and can rely on it being there.

I'm not sure if I've ever lived anywhere else where we see power prices doubling in such a short time. I guess this is one of those changes we aren't going to see with the Carbon Tax.

Hmm ... wonder how I can work smarter on this one?

Friday, 22 June 2012

The gas heating of the floor last nights data

Good morning :-)

this is the plot of no heating

and this is that for heated till bed time

you can see a distinct change in rate of temp loss in the period soon after I shut down heat

so an outcome of ~17.3ºC as an outcome instead of 15.4ºC assuming the same over night temps.

Quick back of the envelope calcs on the gas:
  • based on gas early usage estimates a 9kg will last 11 days (using till 10pm)
  • adding full night probably reduces this to 5 days
  • $20 for a 9Kg cylinder means about $20 a week.
Quick compare to elec tariff 11 = 22c/kWh - $20 would mean a budget of 90KwH
An Air Con system would use of about 6kWh so would be about 15 hours or not as much (based on the AC system that Monica and Bob have on the corner)

Tuesday, 19 June 2012

floor heating - the gas section part 1

This is a continuation of the posts on my floor heating project to heat our home for the least amount of money in the winter.

The Solar component is intended to stop the house feeling like a fridge all through the day (as it tends to do) and bring up the temperature for the duration of the day. This means that we have a higher starting point for the evening cool down. Back when I wrote this previous post I was already wanting to add in gas to heat the water when the sun goes down. Because in my view gas provides the most effective way to store and purchase energy for heating. I can then take advantage of the same water pipes to transfer the energy (from gas instead of solar) into the heating of the floor.

I expected that this would at the very least slow down the losses of the temperature in the house, and hoped that it may actually heat the house. So with my first couple of days of this system going here is my data findings.

The graph at left here shows the ambient outside temperature plot and the inside temperature plot this evening as my gas water heater keeps the water warm that's circulating through the same water pipes which the daytime solar collectors use.

Essentially the losses boil down to a 1 degree loss over 4 hours, however the losses may change more as the outside temperature has dropped from 20°C to 10°C which will probably increase the thermal pressure (meaning the rate of loss will likely increase).

Either way this is a good result for the house as now the floor is comfortable in light sox and there is no feeling of needing to put on a jumper or sit under a blanket while in the house (after all, 20°C isn't really cold)

The system is still under development and needs a number of stages completing. At the moment what I need to do is:
  • construct the electrical controller for the pumps
  • construct a better junction box
  • organize a better location for the water junction box (that'll be under the house and out of the way)
  • work out the optimal timing for the gas heating for economy vs comfort
more as it comes to hand.

Thursday, 14 June 2012

Biggest Carbon polluter

Seems that the National Radio is running an article complaining that an aluminium smelter uses 10% of one of the States power. Equivalent to a million homes.


Well shut it down and then see how many homes also go dark due to no jobs.

What stuns me in this pathetic idiocy is that the focus is never on how can we shift the demands to other sources or how important industry is to a healthy society.

In the past the solution to meeting carbon targets has been shift production to China and then point to them as polluters. The Chinese leaders must be laughing.

What instead we should be doing is to keep production here and work out how to make it more effective. That way we keep the benefits and keep control of doing it right.

There are 3 pillars to sustainable development.
* environment
* economy
* society

All must be in balance.

Stop blame gaming and think about integrated plans.

Thursday, 7 June 2012

observation of the transit of Venus

Sorry that this is 'post the fact' but I didn't see the point in putting it up hours before it was going on (or as it was going on) and with the next one scheduled for 2117 its unlikely that anyone reading this will make use of this information for that purpose.

However there are other events that the sun provides which this technique can be useful for and  I think its important for people to realise that scientific purposed aparatus don't have to be complex.

My method used as its basis a pinhole camera method. However my focal length was very long (about 10  meters). Now while this may seem impossibly difficult its actually not needed to construct anything between the camera 'lens' and the projection surface.

Basically I used a mirror outside to reflect the sun back into my house on a wall and looked at the wall.

So my apparatus was constructed from:
  • a mirror I had handy (in the form of one of my wifes powder cases)
  • a grinder disk to give me a starting circle for the aperture
  • a brass washer to stop down even smaller than the grinder disk aperture


This was then mounted to a ruler with masking tape and then mounted onto my tripod with more masking tape.

This was then projected a spot onto my wall where the diameter was about 11cm and the ingres of venus could be seen

So you can do heaps with bugger all if you want to. This fellows pages has many of the basic calculations you need to adapt this technique for observing all maner of solar events.

My point in all this is to try to pull back from the distraction of technology to the core point that it is Physics (and Chemistry) principles that are showing us the basis of the universe. Computers just assist and augment that.

Tuesday, 5 June 2012

watching things grow - reading numbers

Strangely I often see data representing long term growth represented linearly. Personally I think this is good for 'dramtics' but I don't think it really gives a clear view of what's happening over time.

So I thought I'd toss in a few thoughts on that topic while I wait for an SCP to complete....

Assuming we start with 1 and add 1 to it we get a linear growth of 1, 2,  3, 4 ... which we see below in the figure. I've put in two columns where growth is adding 1 each time and the other where growth is adding 10% each time. When you have 1 adding 1 is really doubling your holdings, but adding 10% isn't.

But when you've got 20 adding 1 is only adding 1 and not really much. I mean seriously if you were out on the town and had twenty bucks adding another buck won't buy you much more.

So 'linear growth' starts to be tricky to comprehend when you get a few cycles into the analysis. In the plot above I've only looked at 30 cycles of of 'activity' and already on the log plot the line of 'linear growth' is seeming to show that reducing importance of giving you a buck when you've got thirty already. The Log plot is however showing a more 'linear' view of your growth ... which is of course because our growth is done in percentages ... which is what a logarithm is all about.

This 'aspect' can be seen clearly when we look over a longer time scale, and adding a buck to what you have makes bugger all difference (but adding 10% is still adding 10%).

So this is why financial analysis should make better use of maths tools to express issues. Assmuming the idea is to communicate something rather than obsfucate something