Search found 3861 matches

by Punx0r
Jan 23, 2018 4:20 am
Forum: E-Vehicles General Discussion
Topic: Wind and Solar vs Coal, Gasoline, Nuclear
Replies: 1400
Views: 28417

Re: Wind and Solar vs Coal, Gasoline, Nuclear

What Tasmania does, or doesn't do, for electrical supply pricing is pretty much irrelevant to any discussion. They only have 500,000 people in the whole market and have the luxury of 85% supply from hydro (when the water doesn't run low) , the big civil works aspects of which started building out 8...
by Punx0r
Jan 22, 2018 4:03 pm
Forum: E-Vehicles General Discussion
Topic: Wind and Solar vs Coal, Gasoline, Nuclear
Replies: 1400
Views: 28417

Re: Wind and Solar vs Coal, Gasoline, Nuclear

Is it possible that the situation with the privatised energy market in two Australian states is not representative of the whole world?

For that matter, how did Tasmania do during the same period?
by Punx0r
Jan 22, 2018 11:29 am
Forum: General Discussion
Topic: Bitcoins
Replies: 151
Views: 8753

Re: Bitcoins

I have access to a twin CPU Xeon e5 2603v4 6-core with 256GB RAM and an Nvidia quadro M4000 graphics card with free electricity that's sat idle 99% of the time. Would this be any use?
by Punx0r
Jan 22, 2018 7:04 am
Forum: Battery Technology
Topic: New battery pack build.....25R, 30Q or VTC6?
Replies: 2
Views: 79

Re: New battery pack build.....25R, 30Q or VTC6?

They are all high quality cells and that you are happy to vary the number of cells to optimise the load on each means picking a clear winner is harder. On a cell-for-cell basis I'd say the 30Q is equivalent in performance to the 25R but with extra capacity, while the VT6 has slightly better performa...
by Punx0r
Jan 22, 2018 6:58 am
Forum: Battery Technology
Topic: Solder longevity on nickel
Replies: 10
Views: 143

Re: Solder longevity on nickel

I had no problem either using electronics flux but the nickel was fresh and bright.
by Punx0r
Jan 21, 2018 10:16 am
Forum: Battery Technology
Topic: Solder longevity on nickel
Replies: 10
Views: 143

Re: Solder longevity on nickel

The solder does look like it hasn't wetted very well (it's standing tall in a blob). So if it was hot enough then it does suggest the surface of the nickel wasn't clean enough. You may need a stronger flux. Although you then have to consider residue causing corrosion.
by Punx0r
Jan 21, 2018 10:13 am
Forum: Battery Technology
Topic: Chilwee lead-graphene battery
Replies: 19
Views: 284

Re: Chilwee lead-graphene battery

It will be interesting to see if these batteries are a genuine development/improvement over traditional lead-acid, or if they're just mediocre tech with graphene powder sprinkled in to hype up the product. If they're no good then as mentioned above, there's probably not anything out there that beats...
by Punx0r
Jan 21, 2018 10:05 am
Forum: E-Vehicles General Discussion
Topic: Wind and Solar vs Coal, Gasoline, Nuclear
Replies: 1400
Views: 28417

Re: Wind and Solar vs Coal, Gasoline, Nuclear

I simply answered Hillhater's question.
by Punx0r
Jan 21, 2018 9:09 am
Forum: E-Vehicles General Discussion
Topic: Wind and Solar vs Coal, Gasoline, Nuclear
Replies: 1400
Views: 28417

Re: Wind and Solar vs Coal, Gasoline, Nuclear

And it's going to get worse when global warming hits 2°C and Sydney and Melbourne start seeing 50°C. If only there was a power source that peaked when the sun is strongest to help offset peak electricity demand due to air conditioning... Well, of course you did the thing that solar PV advocates tend...
by Punx0r
Jan 20, 2018 9:18 am
Forum: E-Vehicles General Discussion
Topic: Wind and Solar vs Coal, Gasoline, Nuclear
Replies: 1400
Views: 28417

Re: Wind and Solar vs Coal, Gasoline, Nuclear

Tasmania, with a whopping 93% RE for electricity generation, a 5cent/kwh feed-in tarrif for domestic solar and the lowest CO2 emissions in Australia. It's also close to the cheapest on your list, and, against some predictions for high-percentage RE somehow seems to be able to keep the lights on year...
by Punx0r
Jan 18, 2018 8:31 am
Forum: Motor Technology
Topic: Idiots guide to water cooled mid motor making
Replies: 102
Views: 4217

Re: Idiots guide to water cooled mid motor making

Fair enough Lars, now I know your experience I think there is little I can add that you won't already know :) I know of mild steel used in cooling systems with only phosphoric acid passivation (minimal protection at best). It works OK with good coolant but can suffer bad corrosion with poor coolant ...
by Punx0r
Jan 17, 2018 6:41 pm
Forum: Motor Technology
Topic: Idiots guide to water cooled mid motor making
Replies: 102
Views: 4217

Re: Idiots guide to water cooled mid motor making

i doubt putting any mild untreated steel in a car cooling system would work even with the glycol corrosion inhibitors. It's common practice to use (internally) unprotected mild steel for pipes in engine cooling systems. The coolant includes additives to protect ferrous metals which protects them al...
by Punx0r
Jan 16, 2018 5:58 pm
Forum: General Discussion
Topic: Alternative current
Replies: 29
Views: 319

Re: Alternative current

It looks like you have both the smaller speakers (which are 4ohm) connected to the left channel of the amp and the right channel is connected to a crossover to the large speaker? if so, that isn't right. For a start, two 4ohm speakers in parallel is a 2ohm load and your amp is rated for 4-8ohm. The ...
by Punx0r
Jan 15, 2018 6:16 pm
Forum: General Discussion
Topic: Alternative current
Replies: 29
Views: 319

Re: Alternative current

Ya but smth is quite strange. When I rise the volume the amplifier there is a moment when the speakers do like a big "boom" and stop playing music. I believe that this is because they are receiving more than 12w. Have you got an explanation to this? Are you sure the 12V power supply for the amp isn...
by Punx0r
Jan 15, 2018 9:25 am
Forum: Motor Technology
Topic: Idiots guide to water cooled mid motor making
Replies: 102
Views: 4217

Re: Idiots guide to water cooled mid motor making

I believe this model of moped is a liquid-cooled 2-stroke
by Punx0r
Jan 15, 2018 5:36 am
Forum: Motor Technology
Topic: How can i control this 15kw motor
Replies: 10
Views: 390

Re: How can i control this 15kw motor

I'm afraid I have no experience using Sevcon controllers, but a few on this forum have, so you might want to search for "sevcon" and see what they say. The diagram above appears to show several methods for driving the motor, with regards to determining the rotor position for proper timing of the pha...
by Punx0r
Jan 15, 2018 5:27 am
Forum: Motor Technology
Topic: Idiots guide to water cooled mid motor making
Replies: 102
Views: 4217

Re: Idiots guide to water cooled mid motor making

These mopeds can be modded to do 100km/h with their inefficient petrol engines so the capacity of the cooler will be enough mated with an OK pump. That should be more than up to the job :) As a sanity check, for the rated output power of the moped, it will put at least as much heat into its engine ...
by Punx0r
Jan 15, 2018 5:17 am
Forum: General Discussion
Topic: Alternative current
Replies: 29
Views: 319

Re: Alternative current

The amplifier already has a potentiometer to limit the output - it's called the volume control... It's a myth that using a powerful amp you will end up unintentionally destroying your speakers - the reverse is more likely. As long as you don't use a powerful amp to deliberately drive your speakers i...
by Punx0r
Jan 13, 2018 1:58 pm
Forum: Motor Technology
Topic: Idiots guide to water cooled mid motor making
Replies: 102
Views: 4217

Re: Idiots guide to water cooled mid motor making

I wonder if they measure cpu die or coolant temperature? There is probably a significant difference (thermal resistance)! Yes, the specific heat capacity of water is very good (and convenient). Vehicles have radiator fans for when stationery, when moving, even at ~5mph, the fan is not required. As a...
by Punx0r
Jan 13, 2018 8:53 am
Forum: Electric Aircraft
Topic: Bell Helicopter electric flying taxi
Replies: 4
Views: 134

Re: Bell Helicopter electric flying taxi

If it's missing all the gubbins that make it function they might as well have claimed it's a time machine.
by Punx0r
Jan 13, 2018 8:47 am
Forum: Motor Technology
Topic: Idiots guide to water cooled mid motor making
Replies: 102
Views: 4217

Re: Idiots guide to water cooled mid motor making

That's bigger than I was expecting for a computer cooler. Something that size should do the job with a good fan or sufficient airflow from forward movement of the bike. Airflow through a cooler makes a huge difference to it's thermal performance and I think the problem with computer setups is being ...
by Punx0r
Jan 12, 2018 8:10 am
Forum: Motor Technology
Topic: Idiots guide to water cooled mid motor making
Replies: 102
Views: 4217

Re: Idiots guide to water cooled mid motor making

There was a lot of discussion a couple of years ago about a proprietary ebike system that used 5 phases. The manufacturer claimed all sorts of supposed benefits, many of which didn't stand up to scrutiny. My recollection is that after a lot discussion and analysis the conclusion was 5 phases over 3 ...
by Punx0r
Jan 12, 2018 4:10 am
Forum: Motor Technology
Topic: Idiots guide to water cooled mid motor making
Replies: 102
Views: 4217

Re: Idiots guide to water cooled mid motor making

I think comparison would be difficult as the motors are different in many other ways that will have effects on performance & efficiency. You'd need identical motors but just wound differently (and I can't think of any examples of this).
by Punx0r
Jan 12, 2018 4:07 am
Forum: Motor Technology
Topic: How can i control this 15kw motor
Replies: 10
Views: 390

Re: How can i control this 15kw motor

Ah, that's good you know it's a Sevcon - hopefully you can find a manual for the dragon8. Otherwise, maybe their other controllers use the same connector? Here's the pinout for the Gen4 model (page 3-11): http://www.thunderstruck-ev.com/Manuals ... l_V3.0.pdf
by Punx0r
Jan 11, 2018 6:12 pm
Forum: E-Vehicles General Discussion
Topic: Wind and Solar vs Coal, Gasoline, Nuclear
Replies: 1400
Views: 28417

Re: Wind and Solar vs Coal, Gasoline, Nuclear

I'm talking about nationwide fluctuations in demand, so it seems you have to have a few coal plants idling alongside your inflexible baseload coal plants to take up the peaks (and presumably you still need to predict the peak well in advance to feed the boiler and raise sufficient steam). Doesn't th...