Kundalini
Posts: 11
Joined: Tue Jan 05, 2016 2:22 pm
Location: Bonnie Scotland

Re: BMW UK i3 REx without plugging in?

Thu Jan 07, 2016 9:42 am

psquare , my figure of up to 70% cheekily guesstimated an additional amount to take into account the horrific electrical losses incurred in its distribution.
If you check the site you mentioned around 6pm on a cold calm day, you may be surprised.
Most renewables cannot be relied upon regardless of the scale of operation.
I totally agree with the benefits to town and city air pollution levels if we were all to drive electric vehicles, i just wonder where the HUGE supply of electricity to keep us all charged up is going to come from.
We could always turn off all the lights and go back to the dark ages :o

psquare
Posts: 476
Joined: Wed Oct 15, 2014 5:57 am
Location: i3 REx, 225xe Hybrid UK
Contact: Website

Re: BMW UK i3 REx without plugging in?

Thu Jan 07, 2016 11:40 am

Kundalini wrote:psquare , my figure of up to 70% cheekily guesstimated an additional amount to take into account the horrific electrical losses incurred in its distribution.


You're right there, but all forms of energy generation have losses.

Kundalini wrote:If you check the site you mentioned around 6pm on a cold calm day, you may be surprised.


As long as YOU check on a windy, sunny day - who knows, maybe you will be surprised too? :)

Kundalini wrote:Most renewables cannot be relied upon regardless of the scale of operation.


Yes, we keep on hearing that, but the progress in wind, hydro, solar and storage will soon eat into these arguments.

Kundalini wrote:I totally agree with the benefits to town and city air pollution levels if we were all to drive electric vehicles, i just wonder where the HUGE supply of electricity to keep us all charged up is going to come from.
We could always turn off all the lights and go back to the dark ages :o


Hey, don't put the head in the sand just yet. Saving energy is more important than generating it. That's where the focus needs to be. Hence the development of the i3, which is the most energy efficient EV to date (well, unless you use the REx a lot).

Will EVs save the world? Of course not. Are they better than ICEs? Most definitely.

Kundalini
Posts: 11
Joined: Tue Jan 05, 2016 2:22 pm
Location: Bonnie Scotland

Re: BMW UK i3 REx without plugging in?

Tue Jan 12, 2016 3:37 pm

Anyway, now my head is back out the sand, to return to the original question which remains unanswered.
Until science achieves what now seems impossible, my best bet and the most ecologically friendly, is to collect water in many large bags from the stream passing under the road near the hilltop and use the extra momentum on the way down to super-regenerate my batteries, negating any losses.
I must remember to dump the water at the foot of the hill though.

EUREKA !!!

The first Hydro-electric-range-extending-never needs plugging in (cos boy am i sick to death of charging the plethora of devices i now need to remember) funky i3.


On second thoughts, i might just hang on to my super efficient 15 year-old petrol driven 3 series (Still has original battery).
What with fuel prices as low as £1.17 per litre of super-unleaded while retaining the ability to drive up a mountain much faster than i would ever dare descend, it would be foolhardy of me to make the switch at this time.

Tongue firmly in cheek,

Peter.

jadnashuanh
Posts: 3187
Joined: Thu May 22, 2014 2:07 pm
Location: Nashua, NH USA

Re: BMW UK i3 REx without plugging in?

Tue Jan 12, 2016 4:01 pm

The REx as a generator will likely never reach the efficiency of a utility fossil-fueled power plant. Throw in that some of that grid power is from clean sources, and thinking that generating it yourself on-site from the REx is more efficient, just doesn't add up to me. Now, should you install some solar panels, you could charge the thing at no cost, other than the cost of the equipment (not insubstantial!). Plus, consider that the REx is a moped motor...it works, but isn't really designed for constant use like an engine in an ICE. Sitting stationary, the heat will likely cause issues if left to burn through an entire tank. Momentarily, as allowed by the current software, not an issue.
Jim DeBruycker
2011 535i x-drive GT, 2014 i3 BEV

Kundalini
Posts: 11
Joined: Tue Jan 05, 2016 2:22 pm
Location: Bonnie Scotland

Re: BMW UK i3 REx without plugging in?

Wed Jan 13, 2016 7:07 pm

jadnashuan, i really only wondered if using the REx as a generator (software permitting) would be more "efficient" than charging using electricity from our National Grid. Who can say for certain? I suppose the answer would depend on which way can be made most profitable.

As an alternative to psquare's earlier link, this site seems to put a different spin on what our green/clean generating capacity actually is here.

http://nationalgrid.stephenmorley.org

There's little doubt any increased "green" demand would be met by "brown" supply.

As for solar panels, they're fabulous if you're in the business of making them or are lucky enough to live in a sunny Country.
I'm afraid to say that the sun don't shine much in this part of the world so they are of little practical use here (unless your in it for the subsidies).

Ta guys
Peter

jadnashuanh
Posts: 3187
Joined: Thu May 22, 2014 2:07 pm
Location: Nashua, NH USA

Re: BMW UK i3 REx without plugging in?

Wed Jan 13, 2016 7:24 pm

A US gallon of gasoline can produce the equivalent of 114,100 BTU, converted to watts, that's 33, 439W. Considering that the usable capacity of the battery pack is around 18-19Kw, and the REx on it's full tank is stated to get you a range increase of maybe 70-miles using 2.4gUS or almost 274Kw , the efficiency is lousy in conversion. You can do the rest of the math. Large utilities are LOTS more efficient, even when you take into account distribution losses. So, Kw/fossil fuel used, the utility will win hands down. Maybe I'm missing something. Throw in any green suppliers, and that tips the scales even further.
Jim DeBruycker
2011 535i x-drive GT, 2014 i3 BEV

Kundalini
Posts: 11
Joined: Tue Jan 05, 2016 2:22 pm
Location: Bonnie Scotland

Re: BMW UK i3 REx without plugging in?

Thu Jan 14, 2016 6:11 pm

I think you may be missing something quite unique to the UK and your figures confuse me (not difficult).
I'm led to believe the UK’s existing nuclear power stations will close over the next decade "all but one expected to stop operating by 2025" and the first new plant not expected to come online till after 2024 (originally planned for 2017).
The UK also aims to close all of it's coal-fired power plants by 2025.
Building more gas fired plants to ensure continued supply seems to be the preferred solution (claimed to produce 1/2 the CO2 of coal fired stations) but with gas supplies increasingly coming from inefficiently extracted, unconventional fossil gasses (Shale Gas, Coal Bed Methane and even Underground Coal Gasification), they bring with them their own environmental HORRORS.
The simplest solution here would be to reduce as much as possible the demand for electricity and in my mind, the rapidly rising use of plug-in electric vehicles can only hinder that.
The i3 REx is almost there, if only it didn't need plugging in.

jadnashuanh
Posts: 3187
Joined: Thu May 22, 2014 2:07 pm
Location: Nashua, NH USA

Re: BMW UK i3 REx without plugging in?

Thu Jan 14, 2016 6:25 pm

FWIW, the bane of the electrical power grid is peak loads. There is often an oversupply overnight when most people recharge their EV's. Power plants that must come on during peaks tend to cost money warming up, or cost money kept in standby mode so that they can come up on grid fast. Much of the problem is that the wind blows more during the day and slows overnight, and solar only works when the sun is out. Over the years, there hasn't been much research into how to store excess production capacity so it can be released economically during peak loads to help keep the production level steady. Anything you can do to shift the load and make it more even means higher efficiency. An EV can help. Making power with current small production sources is not as efficient. You can be fairly efficient on smaller units, but the REx is not in the same league as a utility company's production of electricity except in maybe convenience. There are a few places where electricity ends up essentially free during some hours of the night.

Hydro is good, but not everywhere has enough flow to make things useful. AN interesting technique that has been in use for decades is at Niagara Fall, NY in the USA and Canada. At night, they essentially almost shut down the falls (not readily apparent to the casual eye), redirect the water into storage areas, and then can release it during the day to help if they need a bit more power to be produced while keeping the falls running for tourists!
Jim DeBruycker
2011 535i x-drive GT, 2014 i3 BEV

Kundalini
Posts: 11
Joined: Tue Jan 05, 2016 2:22 pm
Location: Bonnie Scotland

Re: BMW UK i3 REx without plugging in?

Sun Jan 17, 2016 1:57 pm

I've learned a lot lately, so
hear this anyone who's interested.

If the predictions of future power (electricity) cuts here come true,
according to whats shown below, it is technically possible to stay mobile using petrol alone in the REx.
i.e. No additional electricity, so no plug-in necessary "EVER".



------There should be an image explaining everything here but i don't know how to add it ------



Now, when you consider the REx petrol engine is capable of producing 25 Kw then, without restrictions, it could charge the battery pack from 1/2 empty to full in just 23 minutes (disregarding losses and warm up time).
Thats a Rapid Charging station in the boot.

Oil is how much a barrel ? $30/£21/€27.5 and falling ??
That's multiple times cheaper than bottled water 8-)

psquare
Posts: 476
Joined: Wed Oct 15, 2014 5:57 am
Location: i3 REx, 225xe Hybrid UK
Contact: Website

Re: BMW UK i3 REx without plugging in?

Mon Jan 18, 2016 3:11 am

I love it how Llewellyn compared petrol and electric using lawn mowers.

Battery V Petrol. The Lawnmower Test

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