epsilonGreedy

You are going far too deep trying to explain photon impacts and molecular resonance to the man on the Clapham omnibus. Just explain it this way: Planet earth is like a cold blooded lizard which generates negligible internal heat. Only the sun really warms the earth but just above the earth's lizard skin the temperature of outer space is more than 200 degrees below freezing. Fortunately the earth has a few thin duvet covers called the atmosphere. The thickest duvet is water vapour and this is topped up with the CO2 and Methane duvets. For the past 2 million years the earth was a chilly place where ice ages are the norm. Human civilization has florished over the past 10,000 years during a brief inter glacial warm period triggered when the earth wandered a bit closer to the sun and warmed a tad ending the last ice age. Scientists are a little puzzled as to why the earth has not started to cool as we are due to fall into a new ice age. The halt in the typical temperature drop into the next ice age seemed to coincide with humans inventing agriculture which increased the thickness of the methane duvet. Despite being warmed a little by the thicker methane duvet the earth has been cooling for a few thousand years just slower than expected. With the earth's climate teetering at the edge of the next ice age mankind invented the industrial revolution and over the last 200 years the tog value of the thin CO2 duvet has increased by 30% and halted the downward temperature decline into the next ice age. This is fortunate because it will buy humans a few extra thousand years to work out how to manage the climate to prevent the next ice age. If the earth lapsed into a new ice age billions of humans would die.

There is a hole in your explanation. In order for these greenhouse gasses in the upper layers of the atmosphere to radiate out energy into space they first have to capture heat radiated upwards from lower in the atmosphere. In the absence of this point you give the impression that CO2 hovers over the main body of the atmosphere waiting to be warmed by convected heat transfer and then the CO2 acts as a heat export layer by taking over transport of energy out into space at the point where convection ceases to function due to a thinning atmosphere. This sounds a little bonkers because such a mechanism describes CO2 as the opposite of a greenhouse gas.

The second link I posted covered this issue, their initial charge rates were much worse until a test scenario was construed to initiate pre warming. I quoted the pre warmed test results. If we accept that the peak charge rates you hope for will tail off beyond 25% charge and that few will want to arrive at a charge point with under 10% charge and that it takes 20 to 30 minutes to pre warm then in practice I would doubt how often pre warming will apply to a super charger visit. Other Tesla commentators has raised this basic conundrum about the applicability of pre warming.

I have watched a few hours of Tesla Driver on YouTube to be familiar with his youthful verbiage as he pushed auto pilot to the max on difficult Wiltshire roads. He sounds like an excited teenager when the Tesla AP scares him and forces an urgent manual intervention. How would you alternatively describe my "needed to regain manual control" at 3 minutes 30 seconds in the following video? https://www.youtube.com/watch?v=UCZ56T16wvc

That is now routine near London or Birmingham. Our British highway code conventions breakdown when say 5% of drivers passed their test in another country. Yes the American undertaking system works there, the problem is when drivers apply different conventions on our roads.

Most people chose to delegate product reviews to others they trust, for example I would not risk wasting 2 hours of my time viewing a film at the cinema without checking what the BBC's Mark Kermode thinks. James May is hardly a randomly selected online quote of convenience, he is the sane, wise and thinking component of a British car review institution. His critique of the touch screen makes absolute sense, why do you think interacting with a mobile phone while driving is regarded as a dangerous criminal act? Taking a Tesla for a test drive would be a waste of my time, if I had £30k to £40k spare for a Tesla it would go on speeding up my self build schedule. I could not contemplate owning a Tesla with its £200 per wheel tyre replacement cost because £200 = a wall hung Gerberit toilet. My Mokka is not a live experimental technology platform, why would I need a software upgrade. The Mokka is rubbish compared to say a Ford Focus for example the indicators frequently fail to cancel but that will be a mechanical design error in the stalk, however I purchased it for £9,200 with 16k on the clock from a pensioner who had been in hospital for a year could no longer drive. I am content with my Jurassic PV powered steed for the next 5 years. Would I buy an EV? Yes for sure, say in 5 years a time. My acceptance criteria would be a 400 mile range, the cabin and driving sophistication of a Ford Focus, Google's latest auto pilot and £75 tops for a replacement tyre.

That is interesting coming from someone who a few months ago thought auto pilot driving was further over the horizon. ? Were there any anxious moments when you needed to regain manual control?

James May makes the converse point and claims the Toyota offers a more sophisticated experience beyond the woohoo peddle to the floor acceleration of the Tesla. He reckons the touch screen is dangerous.

Tesla owners who measure their charge cycles at home indicate a 70% to 80% efficiency is the norm though that will include DC conversions losses external to the battery as you say. I do know that my iPhone warms with 5W to 10W of charge efficiency losses when charging so I am struggling to believe that even Elon Musk is immune from laws of physics. https://forums.tesla.com/en_GB/forum/forums/charging-efficiency-0 Is such a simple mathematical extrapolation wise? This article hints your 17 minute charge expectation is too optimistic. https://www.extremetech.com/extreme/287280-teslas-quarter-megawatt-supercharger-v3-enables-fasts-model-3-pit-stops This one says much the same in more detail: https://www.motortrend.com/news/teslas-v3-supercharger-tested/ The earlier tests were more disappointing leading me to wonder if Tesla loan out software tweaked demo cars that thrash the battery to obtain a headline charge rate at the cost of battery longevity. Anyhow my earlier assertion that peak charge rates decline beyond 25% charge was sound.

I am puzzled how this is possible. If charging efficiency is 95% that must mean the battery in the Tesla floor plan is cooking itself with 12.5kW of internal heating while charging at 250kW. Reading a little further I gather the peak charge rate tails off above 25% charge capacity. If we assume most drivers will be looking to recharge at 10% remaining capacity, then these rapid recharge rates only apply to quick get me home top ups (300 mile range * 15% = 45 miles). As a comparison at the end of my recent holiday in Cornwall I refilled my Mokka to the brim near Truro and saw 605 miles on the predicted range display, drove home to Lincolnshire via a long dogleg into Dartmoor to look at granite kerbstones. Then drove around locally in Lincolnshire for another two weeks before refilling.

All of our present nuclear power capacity is due to be retired by 2032. The only replacement being built is Hinkley C which is likely to come online in 25/26 though they have already used up all their project contingency while building the foundations. And re. Wind. The headline capacity is meaningless, last month wind generation averaged 7.5GW.

I foresee car usage fragmenting into 3 profiles: Well off people living outside large cities with large plots that can accommodate two driveway BEV charging spaces. Rich city dwellers who desire their own car which will be hydrogen powered. The majority of urban people who will summon a self driving BEV taxi via their mobile phone. The taxi pool will manage recharging at purpose built city centre recharging compounds.

James May mentioned that Germany and another country are way ahead on the hydrogen adoption curve compared to the UK, though a quick Google search indicates even Germany has just 75 roadside hydrogen filling stations. At one point during the video JM explains that the slow Tesla charge rate is because other vehicles were charging concurrently at the same public charge point. Your 900/3000 charge rate ratio is unrealistic because it assumes a 1/4 Mega Watt power cable is laid on to every public charge point. They are niche trickle charge devices. Methanol fuel cells have a limited life span, I think they clog up over 100's or 1000's of cycles.

James May likes his new hydrogen power Toyota. For those not blessed with a brain the size of planet, here is an interesting comparison of a Teslar and a hydrogen fuel cell power Toyota. https://www.youtube.com/watch?v=d2Ovn4REO2w Edit: And here is the Part II road test. https://www.youtube.com/watch?v=GaIW5CQQ3Zo

The forum needs a good definitive reference thread on blocks. When I was starting out in self build I wasted hours online trying to comprehend the scope of blocks available and their pro's and con's.

I wish that was true, in practice things are different. This is the top item in my Google search which happened to be Northampton Borough Council. The policy in Northampton sounds similar my local council. https://www.northampton.gov.uk/info/200028/council-tax/1905/council-tax-new-properties-and-completion-notices

I don't doubt what you say however if council officials pursue a contrary policy then it takes much effort for the individual staring at a final demand to prove their policy is wrong. My recollection of previous BuildHub discussions on this subject is the case law relates to ruins and houses falling into a dilapidated state.

This is a hot topic and is it possible application of the law has evolve since then? I think we slow paced self builders are collateral damage in an ongoing game between councils and big builders who have been slapped down over the disconnected mains water supply ploy.

I registered to pay and was rated as Band A. Not sure about workers accommodation, I assume there is some principal residence test. My local council keeps an eye on new builds and once the windows go in they will levy the full rate of the main house within 3 to 5 months.

I thought new builds are subject to whatever the actual installation cost is?

Thank you for the research, on the face of it that undermines my case. However there is much peripheral discussion on the internet that indicates if OpenReach need access to a property for an install (even just a fly over) this tips rights back in favour of the property owner. Until this week I had not realized what a basket case institution OpenReach is, any political party that promises to eradicate OpenReach by Act of Parliament will get my vote.

Update: Second more senior engineered arrived this morning to assess options. Bad atmosphere still hangs in the air so left angry neighbour and engineer to walk around area looking at telegraph poles and sight lines. After 40 minutes the engineer knocks on my door to give me a summary. My instinct is proven right and confirmed by the people who have to do the job. The single span across the whole width of my plot is too long for regular 4 core cable and a fly over route through trees is a further disincentive. Hopefully another route will be the recommended option. The underlying problem here is that the original OpenReach employee surveyor was out of area, living in a hotel and helping out with an excess local workload. He got too pally with the angry neighbour and another ex. BT neighbour and recommended a bad route. This set expectations for a quick cheap install. Gravity and my protest thwarted Plan-A hence the dispute.

I feel OpenReach is at fault as well because I ended up with just a couple of minutes this morning to make a snap decision about whether to bar access to my plot for the job to go ahead. If they need access surely they should contact an owner min a week ahead of the installation to discuss a way leave. Does anyone know the likely cost of calling back OpenReach in few years to disconnect a 60m flyover connection and then pull the line through an underground conduit dug by me?

This is my one of my actual concerns, if the flying connection goes in and 3 years later the tree brings the line down I am liable unless a way-leave specifies otherwise. Anyhow things took a turn for the worse this morning, just 6.5 days elapsed since the initial OpenReach survey a contractor arrived at 9:30 this morning to rig the line. I told him I was denying access, he takes photos to illustrate the job complexity to HQ and drives off while the neighbour is remonstrating with me about my unreasonable behaviour. "remonstrate" vastly understates the severity of the confrontation. The original surveyor comprehended the complexities of the job and should have flagged the job as requiring a signed way-leave from me, before the neighbour's hopes were raised. Instead OpenReach subcontracted to a non OpenReach outfit. It is perverse that just when some think-time is required a utility company can go from survey to installation in a single week.

I suggested that as we could have shared the cost because I want a french drain in the long run. Suggested flyover route goes through two trees, one is a mature willow and the other is a 15ft high cherry tree. The OpenReach surveyor claimed these would not create problem for the cable. However the willow is due for another pollard pruning which will be problematic once the cable runs through the tree. No the other utilities are connected to that property, all short runs from the public road direct into their plot. The flying BT connection is needed because there is no underground ducting for a BT cable into this new build.