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2·7 months agoThose turbines look interesting, definitely a plausible technology based off that video. Looks like they have used gearing between the two blades to concentrate the energy from both blades so you only need one electric generator (generally just referred to as an electric motor but they do both) which is far more efficient (but still along the same lines of) stacking multiple up using electrical connections like you can do with solar modules to increase power output, which is what I was thinking of when I wrote my previous comment.
It also makes me think of this, https://youtu.be/Qbv_dtwTGDo?si=fSpRWpGqBlTEjMqH, which seems like a decent idea to me.
I’m not sure if it is a lack of feasibility that is getting in the way or just a lack of political will and interest. Could even be because solar is so cheap now that a newer, less refined technology (even in terms of legislation and infrastructure planning) with higher up front costs is just less desirable. I think I could still be worth investing in both in the long run (assuming it is actually viable).
I don’t know heaps about them directly, but in terms of rooftop VAWTs I guess it could depend on the type of roof, and ultimately the amount of wind that the rooftop will be exposed to.
It could be more challenging to create residential scales VAWT than it would be for commercial buildings such as the ABC building you mentioned (don’t know it off the top of my head but I’m assuming it is a least a few stories tall). I’d say a reason for this could be that as the amount of wind the turbine is exposed to reduces, so would the size of the generator, to ensure the force of the wind on the blades can generate enough counter-torque to get the blades moving and therefore generate power. Using smaller motors would definitely be possible, but you might reach a point where the amount of materials needed for each small-scale VAWT outweighs the amount of return through energy generation of each turbine, because the motor is so small, and counter-torque so small that the motor turning would only generate negligible amounts of power. EDIT: Forgot to add the context of I think there is generally more wind at higher altitudes, whether this is an in general rule or relative to the surrounds (like being in a valley vs being at the highest altitude in the region; or if you are in a low density township vs if you are in a density populated city with more structures blocking wind) I’m not certain, but it is the context for why I said residential rooftop VAWT may end up having far lower generating potential that commercial rooftop VAWT, because I’d say there is more wind on the roof of a commercial building than a residential one.
I would guess the large horizontal axis wind turbines would use large AC induction motors to generate the electricity as the blades turn. I would guess that AC motors would have some size limitations (easier to make really big ones than really small ones, not to say really big ones would present other challenges, but it would be incredibly challenging to make them under a certain size due to all the copper windings that need to fit in the motor) so once your VAWT reaches below a certain size a DC motor would need to be used. This introduces further complications, as our grid runs on AC, any DC power generation first needs to be converted to an AC waveform for the power to be injected in the grid (or used to power a load connected to the grid). This process is already performed for solar using inverters. It would also be performed for HAWTs (probably both AC to DC conversion followed by DC to AC conversion) to ensure the output (voltage, frequency, power factor) matches the grid.
It gets more complicated though, as inverters have an allowable operating DC input voltage range (these can be quite high voltages as you can place solar modules in series to increase the voltage of the generation. For example, if you put two solar modules, each with an operating voltage of 50V (arbitrary number) in series, the total voltage of that series connection will be 100V). This allows larger inverters to be used. It may not be as easy to utilise larger inverters in such a way with VAWT unless you scale up the number of them as using inverters for each individual small-scale VAWT could mean the use of a lot more materials. EDIT 2: There are cases where small inverters (known as micro inverters) are connected to every solar module in an array, so it could be argued you could do the same with small VAWT. There are also things called optimisers, which i think essentially perform the operation of a chopper (described further below) changing the DC voltage to match all the other modules before connecting to an inverter. Both of these option involve extra costs when compared to direct connection of entire strings (described further below) of modules to an inverter.
Considering using VAWT with batteries will also have added complications. Batteries store DC energy, so an AC to DC conversion would not be necessary to charge the batteries, but you would most likely still need DC to DC conversion (from memory they are called boost/buck choppers) to increase or decrease the input voltage to match the battery terminal voltage (a lot of solar inverters that can connect to batteries most likely already have these installed internally). These boost/buck choppers also have voltage input limitations, meaning they won’t operate if the input voltage is too low or too high. Therefore, to be able to use both solar and wind on say a residential rooftop, it may mean the installation of more, or retrofit of existing electronics so the power waveforms of both the solar modules and the VAWT can be transformed to match the grid or battery power waveforms. I think it’s probably unlikely that a smaller VAWT could match the voltage of multiple solar modules connected in series (known as a string), so either a second chopper would need to be added which can transform DC waveforms from a much lower voltage to match the battery terminal DC voltage (vs comparing the voltage difference between the solar string choppers input/output voltages), the choppers in the inverters would need to accept a far greater input voltage range, or as I said above, you would need to connect multiple small-scale VAWTs together to develop the necessary power waveform.
This may be one of those things where if we started designing/building/installing small-scale VAWTs about a decade ago there may have been more incentives for inverter and battery manufacturers to enable VAWT connections through the same hardware, or could be something we could consider if Aus goes down the inverter/battery manufacturing path in the future.
It could also be possible that people in the relevant technical positions have already considered all of the trade off’s and they just don’t add up to make small-scale VAWTs viable. This could be why we rarely hear about them. These things can always be subject to change though as technologies and manufacturing processes improve and change, and materials costs reduce.
Pervoskite still has some challenges to overcome before it can be a primary material in solar modules. One of the major problems being Potential Induced Degradation (PID) which is ironically caused by sun exposure, and leads to decreased power output from the solar cell. https://www.sciencedirect.com/science/article/pii/S2666386422003174
The market is currently looking transitioning from p-type modules to n-type (both crystalline silicon based). P-type was the market leading technology for many years because issues like PID, Light Induced Degradation (LID) and Light and Temperature Induced Degradation (LeTID) were more easily resolved in p-type modules. N-types (also known as TopCon) are taking over now as these issues are being resolved and n-types are capable of reaching higher efficiencies than p-types. The higher power classes of n-types (>= 430W) over p-types (peaked around 415-420W) [these power classes are from modules designed for residential installations so have a surface area of about 1750mm*1100mm] is also enabling people to claim the maximum rebate for installing solar on their residence. This is because there is a rebate maximum that is based on installations up to a total size, and the newly released n-type modules (have only been in the market a little over a year) have a power class (440W) that divides evenly into the max installation size (6.6kW) so people can claim the entire rebate.
It looks like the manufacturers are looking to work towards developing hetero-junction (HJT) solar cells. There are a combination of both silicon and pervoskite, with the intent to be to make the most of both materials properties to improve module efficiency while also keeping PID, LID and LeTID within reasonable levels across the module’s lifetime.
Edit: just adding some more citations. I haven’t directly quoted from any of the sources, just regurgitated info from my head and added them for further readings. Information above may be subject to some inaccuracy. https://www.solarquotes.com.au/blog/p-type-and-n-type-solar-cells-excellent-electron-adventure/
https://www.maysunsolar.com/blog-n-type-solar-cell-technology-the-difference-between-topcon-and-hjt/
https://www.nrel.gov/docs/fy21osti/78629.pdf
https://www.pv-magazine.com/2019/03/12/lid-and-letid-qa-with-jinkosolar/
Edit 2: grammar/spelling
1·10 months agoI’ve been considering calling the platform FascX. Not sure how well it works though.
I would assume that none of us find Peta Credlins political leanings to be surprising, but I am hopeful it may be starting to more apparent to the general public.
I think the answer to the headlines question is easy, there is a strong possibility Credlin is a Murdoch shill, and protentially always has been. If you haven’t already you should watch ‘Nemesis’ on the ABC about the LNPs tenure from Tony to Scummo.
During Tony’s tenure, he keeps getting more and more advice from Credlin, or only discusses issues with her, and ignores the position of the remaining MPs in his party, prioritising Credlins positions. After Tony got toppled, all of a sudden you see Credlin on Sky News as a host dishing out opinions about the direction the country should take and screeching whenever the government goes against those ‘opinions’, as sky news does.
According to the below report from the guardian, there was a rumour floating around that Sky News offered Credlin a position after she left the Fedral government when Tony was toppled (published 21/3/2016):
https://www.theguardian.com/media/2016/mar/21/the-bolt-report-to-be-resurrected-on-sky-news-five-nights-a-week?CMP=share_btn_url
Followed by this article 10 days later (31/3/2016): https://www.theguardian.com/australia-news/2016/mar/31/peta-credlin-joins-sky-news-as-2016-election-campaign-commentator?CMP=share_btn_url
I also found this statement from the above article very interesting, though I can’t say it is still the case as these articles are from 8 years ago
Credlins Wikipedia page states:
And has her credentials listed as:
https://en.m.wikipedia.org/wiki/Peta_Credlin
This is potentially a better source, or a least is a second source giving the same info:
https://www.mckinnonprize.org.au/panellists/ms-peta-credlin/
The below article refers to a book written by Niki Savva who, according to Wikipedia, is an author/journalist and former senior advisor to Johnny H and Peter Costello. https://en.wikipedia.org/wiki/Niki_Savva
And naturally some heavy hypocrisy from Peta in her response
https://www.theguardian.com/australia-news/2016/mar/06/abbott-and-credlins-destructive-approach-led-to-downfall-says-author?CMP=share_btn_url
There is also this article from 2014 (published 24/2/2014), though the article doesnt go into a great amount of detail, and the link to another report in it is broken, but at the same time AFR is a fairly right leaning publication and it doesnt seem Tony sued them for defamation, which seems to be the general way people in the political class seem to want to obfuscate their involvement in such things. I guess he wasnt as concerned about his hat as Bruce was:
https://www.afr.com/politics/federal/news-to-me-abbott-says-of-882m-cash-for-murdoch-s-news-corp-20140218-ixrok
And then there is when Tony made comments like this in 2014 (published 16/7/2014):
https://www.smh.com.au/politics/federal/tony-abbott-praises-the-australian-as-rupert-murdochs-gift-to-our-nation-20140716-3bzwg.html
Now, somewhat unsurprising, Tony was offered a position on the Fox News board of directors in 2023, which he accepted, because supposedly Australia’s LNP MPs are all experts in media and therefore deserve to have obtained these prestigious positions within News Corp without any prior experience in media. Oh whoops, my mistake, according to the below source (Fox’s own website), Tony worked as a journalist at The Bulletin and The Australian (strange he worked for these institutions prior to entering parliment according to the below):
https://www.foxcorporation.com/management/board-of-directors/tony-abbott-ac/
So, there appeared to be a strong relationship between Tony and Murdoch before he was toppled as PM, potentially even going back to before he entered politicas, according to Fox itself. The person who Tony was closest to in the parliament (which, again, can be seen documented further in ‘Nemesis’), his chief of staff, an employee of the government, not an elected official, were making decisions for the majority of the party and direction of the government, without consulting the rest of the party’s elected representatives, which is, you know, the whole point of having political parties and representatives in a democratic nation.
While none of the above conclusively connects Credlin to Murdoch prior to her being hired by Sky News in 2016, I think it definitely leaves questions needing to be asked about Credlins credibility throughout her political career, her subsequent career as a political commentator, and what has now been further demonstrated as her having direct connections to members of the VIC LNP, who she is actively “dispensing advice from the sidelines” to.
Who knows, maybe she is just a useful idiot who got hired to be a commentator by Murdoch after she demonstrated herself (the Barrister and Solicitor) to be such a useful idiot, under the other useful idiot Tony in parliament, and it was just a match made in arrogance from then on. But I think there is also fair reason to suspect that she wasn’t just a useful idiot, and was instead complicit in everything, but I can’t say (or demonstrate) for certain (please don’t sue me for defamation Peta, I havent stated certainities, just speculations, plus your hat isn’t that important).