if you dont believe in global warming sign this

[damian]

Something else I've been thinking about lately. For some reason you can buy solar cells for about $1/watt but solar panels are about 3 times that, so for the sake of making a shallow box you can save considerable money.

The other big issues with off grid solar is batteries, but there is an alternative: air tanks.

If you run your solar power straight into a dc motor, couple it to an alternator (415 and take off phases as required) you get a fairly efficient converter, then with a couple of clutches an air pump, an air motor and a BIG accumulator you tap off excess PV generation then drain it back through the air motor as required. Because the process is slow you don't get unmanageable heat loss and while it's not 100% efficient, or anything like it, it's probably equivalent to the 50odd% you get with conventional batteries and the pressure vessel will probably last longer.

I haven't done the sums yet, let alone quoted the system up, but it might be feasible.

[damian]

He also made a bit of a hash of his stoush a few years back with the Creationists. Plimer is a brilliant Geologist but he has an almost fanatical hatrid of Creationists and Anthropomorphic Global warming.....it's this IMHO that trips him up.

Yeah he's not great, but he's also fighting fire with fire.

Thing is when I did research I kept all my raw data and methodology and made it available for anyone seeking to scrutinise my work. Most of my peers did also. I am discovering that much of the raw data this stuff is based on is unavailable, and what has "leaked" into the public view is, well, confusing. I'm all for data manipulation where it's justified, but from what little I've seen the manipulation that has been applied, well, it's hard to justify or understand unless you accept an ajenda. The other day I noticed a lot of the historical data has disapeared from the bom website. I wrote to them and they not only charge for it now, for some reason it's truncated. Ipswich weatehr station was established about 1860, yet records are only available from the 1960's ??

(I just tried to check the date and the page is broken, I'm about to reboot so the 1960 thing may be wrong, I'll edit this after I reboot and get the number)

[kiwigeo]

Yeah he's not great, but he's also fighting fire with fire.

This is not the right approach for someone who calls himself a scientist....and its just plain bad PR for the global warming sceptic camp. It's a bit like punishing someone for engaging in violent activity by thrashing the living daylights out of him/her.

Plimer makes a big thing about scientists on the IPCC not being open and attempting to supress the process of peer review. At the same time here we have Plimer refusing to answer very direct questions regarding a number of factual discrepancies in his recent book. It's this that makes him just as guilty of dodgey science as the IPCC scientists he's having a go at.

Your air tank idea sounds interesting....would be interesting to see the figures on energy loss during the process and also the implications of more moving parts.

Cheers Martin

[damian]

The efficiency of the motor and alternator is easy, if you want to be obsessive you can get 93%ish with rare earth magnets but then you've got return on investment issues. The pump/motor has efficiency issues, but the big thing is the heat loss and the cooling as you compress and expand the gas, and this varies with the rate of pressure change.

Air reserviors have been used for storage of generated electricity before, in paris about 1900 ish and apparently the americans are employing it in some places, but both those used abandoned air tight mines and caverns to store centrally generated capacity. If you reduce scale and slow the process it _should_ be viable. I like avoiding the expense, pollution issues and the finite lifespan of batteries, but what I'm suggesting is no secret and if it were very much more efficient/cost effective it would be widespread. Also the accumulator needs to be large and probably the pressures large. You cna also do what they do with town gas accumulators, make a big heavy inverted bucket, over a body of water. That makes for constant pressure.

1965 - 2001. Very disapointing. I've written to ask about the rest of the dataset.

Yeah he doesn't debate well. This site has some fairly rational discussion:

Watts Up With That?

[artme]

Just wondering about what is called "load shedding". I remember when Pat Hills was part of the NSW. Gov. years ago he was always talking about load shedding when we had power problems.

My brother has a high powered ( pardon the pun ) mate in the electricity game. He was saying that one of the massive blackouts in the States some years back was due to excess power being generated for the current needs. Rather than "shed " the load the utility companies took the view that "shedding" was wasting money. The result was action too late and the system blew apart.

[Sebastiaan56]

Air reserviors have been used for storage of generated electricity before, in paris about 1900 ish and apparently the americans are employing it in some places, but both those used abandoned air tight mines and caverns to store centrally generated capacity. If you reduce scale and slow the process it _should_ be viable. I like avoiding the expense, pollution issues and the finite lifespan of batteries, but what I'm suggesting is no secret and if it were very much more efficient/cost effective it would be widespread. Also the accumulator needs to be large and probably the pressures large. You cna also do what they do with town gas accumulators, make a big heavy inverted bucket, over a body of water. That makes for constant pressure.

Then there is salt Sandia National Laboratories - Solar Thermal Designated User Facilities Ona a related page there was a comment that 50% of US electricity was wasted being pushed around. This kind of technology would get rid of that problem but would be much harder to squeeze monopoly profits from. Worth pursuing but I am no engineer. Got to be a giant business opportunity.

[hughie]

Then there is salt Sandia National Laboratories - Solar Thermal Designated User Facilities Ona a related page there was a comment that 50% of US electricity was wasted being pushed around. This kind of technology would get rid of that problem but would be much harder to squeeze monopoly profits from. Worth pursuing but I am no engineer. Got to be a giant business opportunity.

[/QUOTE]


Tesla, the inventor of Polyphase power always said the transmission of power via wires was the most wasteful way to move it around. He advocated doing it differently and he also wanted to give it way for the betterment of mankind. I gather J.P.Morgan his then benefactor thought other wise.

[damian]

I didn't find the article, don't ahve time right now, last day before hols...

Anyway, those sorts of analysis are easily manipulated. The reality is all grids lose power over distance, and the loss is signifigant. Initially electricity was generated close to the point of use but as the smoke from city power stations became politically unacceptable people voted to increase the pollution in order to push it out of their own backyards. Stuff like PV and bluegen are driving generation back to point of use and gleaning efficiencies because of that.

Some friends and I did an envelope calc some time back on pollution loads of trains vs cars. It is quite clear mean distance to power station was a big factor in the calc. Our ballpark figure BTW was 55 people per carraige on full size electric trains vs 1.4 per car (or 1.2 can't remember). I'm a bog fan of busses because of shared infrastructure and flexability in both routing and frequencies of service matching demand.

I can't remember the number, but something like 5% efficiency reduction on mean distance from generator to point of use in australia. That number could be wrong though.

[damian]

Tesla, the inventor of Polyphase power always said the transmission of power via wires was the most wasteful way to move it around. He advocated doing it differently and he also wanted to give it way for the betterment of mankind. I gather J.P.Morgan his then benefactor thought other wise.

Tesla was either the most brilliant genius in human history or a nutter, depending on who's version of history you believe.

He certainly DID invent numerous brilliant things and his life and achievments are well worth reading up on.

[Sebastiaan56]

I can't remember the number, but something like 5% efficiency reduction on mean distance from generator to point of use in australia. That number could be wrong though.

I'll look it up in my Renewable Energy course notes, it is a lot, I seem to remember 40% but that is averaged, eg Hunter Valley to Sydney. Interesting calcs about buses,

[damian]

But does that include other losses ? See you've got big losses at the boiler, smaller at the turbine and generator, losses in transformers and of course lines. The number depends on which parts you include.

I'm a mech eng and I know enough to know I can't do as good an analysis as an elec engineer, but also that EVERY situation is different. Putting a generic number on it is the same sort of stuff the climate change non-scientists try on to snow everybody...

Nice segway back to the origional argument don't you think ?

[Sebastiaan56]

But does that include other losses ? See you've got big losses at the boiler, smaller at the turbine and generator, losses in transformers and of course lines. The number depends on which parts you include.

so lets agree on 2%

I'm a mech eng and I know enough to know I can't do as good an analysis as an elec engineer, but also that EVERY situation is different. Putting a generic number on it is the same sort of stuff the climate change non-scientists try on to snow everybody...

Nice segway back to the origional argument don't you think ?

roflmao....

[hughie]

He certainly DID invent numerous brilliant things and his life and achievments are well worth reading up on.

[/QUOTE]


Yep I can list over 150 patents to his name in various fields