Posts by Aidan
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Hard News: Dirty Politics, in reply to HORansome,
I’ve bene thinking that myself: I think people often forget that the initial reports by Woodward and Bernstein were pooh-poohed by the major newspapers and TV news networks at the time. It took time before the claim of conspiracy was vindicated and become commonly acknowledged as being the best explanation of the event.
This is Robert Redford’s take on Watergate.
https://soundcloud.com/aidanh-1/robert-redford-on-watergate
Same old same old – cynical “in” journos who are are just too smart for their own goddamn good.
Woodward and Bernstein were the outliers, the ones prepared to really take it to the powerful. Rest too scared, too "savvy", as Jay Rosen might say.
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Another thing to carefully consider is the size of the water tank you attach to your panels. Often people are advised to get a larger tank as it can store hot water for longer, potentially covering for a cloudy day or two. The danger of too large a tank is twofold: not being able to heat the large mass to a high enough temperature, and having to boost a large volume of water on cold winter days.
A properly designed tank can have the booster heating element placed higher up, so when it does boost it is only heating a smaller volume of water. Again, it relies on stratification.
I believe that newly installed electric boost systems here in Canberra are no longer allowed to turn off their booster, as they are paranoid about legionella. This is unfortunate, as it will be a great deal less efficient, harvesting much less solar energy if the tank is always maintained at 60 degC. Not sure what the regs are in NZ.
It might also be worth it to lag all your hot water piping while you’re redoing things. Especially if the new system is located further away with longer runs of piping. Make sure they use the plastic coated pipe lagging for exterior work exposed to UV. The other stuff breaks down very quickly in sunlight.
We also had to have a tempering valve in our setup, which we had never had before. Again, new regulations. This drops the outlet temperature to 50 degC to prevent burns, but it also meant we had lukewarm water in the kitchen in winter, until we lagged the pipes.
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Bit late, but we've got a 30 tube/250L electrically boosted system. Here in Canberra (more like Christchurch weather, hotter in summer though) we don't need to boost Sept->Apr. We've got a timer switch in the fusebox for the electric boost, and it comes on from 5.00-6.20pm, and it will top it up if we've had a poor solar day.
We have hard frosts, so the tubes make much more sense here. People on various enviro forums reckon you get a much bigger surface area for panel systems for the same cost, so if frost isn't an issue this is a better way to go. Also the integrated thermosiphon jobs are very well understood, very low tech (I've been quoted $1000 to replace the controller on our system, which is outrageous. I wouldn't pay that, but it gives you an idea of what some are paying). Don't write off flat panel systems, but I don't know enough to recommend any.
Your water use patterns matter a lot. If you all tend to shower at the same time of day it helps. We scrub the kids in the evening, but the adults are morning showerers. This means the tank is half full of cold water overnight. It is supposed to stratify and not mix too much, but it still has an effect.
We tilted our tubes up to 50deg, as we have an over-production in summer, but our shoulder and winter production was disappointing. There was a substantial improvement after tilting, with the added bonus of less over-heating and venting in summer. A wetback + solar system would be a great combination, as a solar system sized for summer will struggle in winter. Sized for winter it is likely to be expensive and still struggle on very cold dull days.
We average about 5kWh/day electricity usage in Summer, 8 kWh/day in winter.
We also have a 1.5kW PV system. This produces about 2/3 of our power, but as we got in when there was a generous FiT, we don't pay power bills, they pay us.
CAUTION: PV does not like shade! If there is ANY shade on the panels your output will be substantially reduced. The cells turn into resistors when shaded, so well designed panels have by-pass diodes that, as you may have guessed from the name, bypass that section of the panel. All it needs is a small part of a panel to be shaded to bypass a much larger area of panel: there is a limit to the number of bypass diodes. Upshot of this is you can have a quarter of your panels shaded, but get a 75% reduction in output. It depends very strongly on the geometry of the panels and how the shade interacts with that geometry.
If you have significant shading from 10am-3pm I think PV would be a mistake.
I understand thin-film PV suffers less from shading (and possible also better in overcast conditions), but I haven't done any significant research into that.
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Southerly: Who was George Hildebrand…, in reply to Annie Magee,
1898/3379 Eliza Ann Winter Frederick Kennard
Sorry to be a pain, but another weird coincidence, I married a Kennard (not in NZ), Names eh? Maybe not as rare as I'd imagined ...
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Off topic, but my Grandmother was also named Winifred Beatrice (b. 1910). No connection to this story, but just an odd coincidence.
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Hard News: Circumstance and coincidence, in reply to Russell Brown,
Does he always issue such terse replies or just seeking to deny oxygen/not get caught in lie?
Is there no mechanism for a "question on notice" or require an undertaking for the PM to actually make some enquiries with departments etc to find out actual information?
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Hard News: A Big Idea, in reply to Idiot Savant,
Because stock market bubbles are so much better than property market bubbles.
Note that Germany has rules about corporate governance that give workers input into the running of the company. Apparently this is a major reason German companies are "valued" less on the stock market. I don't know if this would tend to suppress some bubbly aspects of the stock market, but as it has already depressed values it clearly has some dampening effect.
Note that the firms themselves are no less profitable or valuable in toto, it's just that some of the value is held collectively in the form of employee control.
I'd also point out that capital investment does not equal buying shares on the stock market. Companies issue debt or extra shares to raise money for economically useful purposes. The role of government is to set policy to make it more attractive to socially useful stuff with the money than bid up the price of housing in inner city Auckland.
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Germany has low net wealth, half that of Greece & France, less than a third of that in Spain. Weird eh? Turns out a good deal of this is due to rules and regulations that favour capital investment over fetishistic home ownership
Wealth is a social construct. Policies can change wealth, which can change investment incentives.
Maybe high house prices are a result of secular stagnation. If so, those other articles might hint at approached to reconfigure the incentives to make capital investment more attractive.
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That is some awesome work.
Remember what that venerable old DIYer Voltaire said when trying to fix a nasty case of rising damp in his Covent Garden bedsit
"The perfect is the enemy of the good"
You're also in danger of becoming an expert in something you really don't want to do.
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Does NSA count as a word?