Vehicle to grid becomes a reality in the UK

 This idea has been around for a while, and it's interesting to see it coming to fruition.  Many, many years ago at uni we studied combined heat and power units (CHP), essentially boilers that would generate heat and electricity. The concept being that reducing the load on the electricity grid and generating power in-home would significantly change how we produce electricity in the UK.

Currently the power grid is (and has to be) designed to meet peak requirements, the example that was given while I was at uni (c30 years ago!) was that during half time in the FA cup final, everyone watching (c20million back in the day) would suddenly boil the kettle generating a huge peak load.  Now things have changed and my kids hardly ever watch linear TV, I guess this scenario has changed, but the concept still stands!

Even just regular day to day use creates significant peaks, for example when it gets dark we all turn lights on, and typically domestic power usage is lower during the day with people being out at work.  All this means that electricity usage is very uneven, meaning power grids have to be provisioned for way above the average load.

The chart below show average household demand (kW) across an average household in summer and winter.  You can clearly see that there is a peak in the morning (around 8am) and another extended peak in the evening between 5-9pm.  These peaks are 3x or 4x the usage compared to when most of us are sleeping (midnight to 6am)

 

 Average UK household electricity demand against time of day for weekdays and weekends in mid-July and mid-January, as synthesised by the CREST Demand Model. No solar PV. Demands averaged over 5 weekdays and 2 weekends in each season, for 15,000 households.   Data from - www.researchgate.net

What Vehicle to grid technology has the potential to offer is to smooth those peaks and troughs.  Imagine that overnight or during the working day (domestic quieter periods) the grid charges EV's, and then in the evening we plug our cars in the power our houses, and then recharge during typical sleeping hours.  Then our EV's become large portable batteries, helping smooth out peak loads.  

This Yahoo article ( Link ) notes :

"A typical electric car can store between 70 and 80 kilowatt hours (kWh) of electricity, while a home typically uses about 15 to 20kWh per day"

This technology can also be extended covering power failures, although technology and legislation need to catch-up first before we can take advantage of this.

So if we can reduce the UK peak load, this means we need fewer power stations, which hopefully means more renewables, less reliance on energy importing, and lower greenhouse gas emissions.

Octopus should be commended on this initiative and hopefully it will extend to more EV manufacturers shortly.

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UK NCSC's Protective DNS service

I have done some work as part of my day job with the UK NCSC (National Cyber Security Centre), they have always been great to deal with, and all the people I've met have been very passionate about protecting the UK from cyber threats.

They have a number of services that I'm not sure get the recognition or usage that they should.  At work we use their Early Warning system, that does a simple daily (I think) perimeter scan of your IP addresses to try and find vulnerabilities. We have had a recent alert for a NetScaler vulnerability that was very timely (we were already in the process of patching it). I highly recommend this free service - link here

They also have some good incident simulation tools, I've not personally used them, but their Exercise in a box is another free service for running desktop drills for cyber incidents.  One of the key steps we tell our customers to take is to practice for events like a ransomware attack. Building up a muscle memory of how to react or at least planning for that event makes it much less scary if it ever does happen. Link here

However the point of this blog post is that last week the NCSC released another tool to help schools last week. This is a protective DNS services, which in essence replaces an ISP DNS services, and will filter out requests to known malicious sites.

As the NCSC says :

" PDNS is already a tried and tested solution as it’s been freely available to organisations like central government, local authorities and devolved administrations for several years "

It's a simple configure once service that's invisible to the end users, but provides an additional level of security. Kudos to the NCSC for rolling this out further.

We did look at offering this to our customers, but asking SME's to reconfigure their ISP's router settings proved to be too complicated to do in a simple and scalable manner.

However there are a number of similar services that are available to home users for free. Google, Cloudflare and some of the other large internet scale companies offer a free service.  Most of these are based around performance rather than security benefits, but there is quite a wide range of options. I found this article really useful, it's a couple of years old now, but provides a good in-depth comparison.

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Repairing a Boston Acoustics Micromedia subwoofer

 I've had my 2.1 computer speakers system for a very long time (I knew this as I bought them when I was at my old company, and I've been at my current employer for 17 years.  But when I actually disassembled the subwoofer, it has 'May 1997' on it, so that's a good 26 years service, so not unreasonable for it to have it first problem

Over the last couple of weeks there has been a nasty vibration at lower frequencies, annoyingly just in the range of some peoples voices, so when spending the day on video calls it was getting a little grating.

So first point of call was internet research. I didn't actually find anything that useful, but there was this YouTube video, which isn't very illuminating, but there were other references to speaker surrounds that had perished over time.

This is the same system as I had. So I started taking it apart (4 crosshead screws, one in each corned - you can see them recessed).  This allows you to take off the whole front of the subwoofer.  However I couldn't work out how to give myself enough room to inspect the subwoofer closely enough.  I couldn't work out how to get the front off as it the video (I still don't know how it was done in the video) .  For me the sub cable had no slack and I couldn't stretch it from the back of the enclosure.  So as it wasn't working properly and I'd had it for 26 years, I thought I'd nothing to lose by cutting the cable. I reasoned that I could always extend the cable and connect it via some sort of cable connector.

Once I'd cut the cable this is what I found :

Left hand image is the rear of the front panel, you can see the cut speaker cable and the bass port which fits into the hole above the sub. You can see from the photo on the right that the subwoofer speaker surround has perished, and therefore this was the likely cause of vibration. 

The photo above shows the problem most clearly,  you can see the near side of the speaker surround has completely perished, but the actual cone (made of paper I think) is still in good condition.

So more internet searching suggested that either Ebay or a company called North Speaker parts could sort out replacement surrounds.  I went with North Speaker parts, as they were UK based, and seemed to be a specialist.  So for the princely sum of £8 I ordered a 5" foam speaker surround replacement kit. This included glue, brush, instructions and 2 new surrounds (even though I only needed one) - kit from here. They arrived neatly packed two days later, very happy with their service.

So as per the North Speakers instructions, with the careful use of a Stanley knife, and rubbing alcohol (we used nail varnish remover) we managed [I enlisted the help of my son, hence the we] to get the majority of the old surround off.  having done that helpful teenager then applied the glue to reattach the cone to the new surround.  Allow that to bond, then an hour later he glued the cone/new surround to the brass frame.  This is more difficult as there's much less space to work with, and it took a while for the glue to actually stick to the new surround. We let this set overnight.

In the morning we checked our work, and it looked pretty promising

So while son was working on the speaker I was working on the cabling. I had spoken a while ago to our plumber and he was raving about Wago connectors. This project looked like a good opportunity to try them out, so a quick trip to ScrewFix for a pack on 100 (not sure I'll ever get through even half of these). I went for these ones - link.  To be honest their blurb says halves the time to make connections, but I found them a real pain (could easily be user error), it could also be that they are designed for solid core mains cable, in which case I can see it would be much easier.  However I had stranded cable, and it probably took me about an hour to get the 4 connections working ! (again could be user error!).

However finally we got it all together, you can see in the photo below a couple of the wago connectors and the sub back in situ.  We tested it like this and there was still some vibration, so I was a bit worried that we hadn't succeeded, however when we screwed it all together it all sounded good ! It's not perfect - when I really turn up the bass there is still a bit of vibration, but at normal levels it sounds perfectly fine. 

I'm really happy how it worked, and my £100 investment (I can't actually remember what I paid), is still going strong. Slightly weird to think I bought this setup before I met my wife, before we got married, before either of the kids arrived, and it's still going strong !

Thank you Boston Acoustics for making such good kit ! and hope this article is useful !

Finally a well earned beer after the project...

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VAR shables - blaming human error is missing the point

Definitely a systems failure !

I've been meaning to write this article for a few days, and in the time I've been thinking about it, Matthew Syed has written a piece in The Times with a very similar perspective.

He's written a book along similar lines, and that book (Black Box Thinking) references a really great book by Atul Gawande called The Checklist Manifesto, which is a fascinating read.  It talks about how the medical profession has learnt from the aviation (and space) industries about the use of checklists.

In The Times article Matthew Syed references Chesley Sullenberger the pilot who landed US Airways flight 1549 on the Hudson in the US in 2009.  What is amazing is the calmness and ability to follow a checklist to avoid any human frailties or individual errors.

What's clear in the VAR incident where the VAR team gave the wrong decision, is that there was no process or checklist to prevent an individual failure.  The PGMOL should have come out and said we had a process failure rather than an individual human failure. For a game that doesn't suffer from being underfunded, the whole implementation of VAR is poor.

As Syed says 

" Instead, given that football is the greatest game on earth and people in football obviously know more than anyone else, they decided that they would do it their own way. We may call this “football knows best syndrome”

He goes on 

"Football, let me suggest, is hubris institutionalised. Its masters assume that because the game is (to some people) a religion, they are gods. I was against VAR from the outset, by the way, fearful that it would destroy the spontaneity of a fast-flowing game but not even I could imagine how poorly it would be implemented. The Premier League, in their infinite wisdom, took no time to learn lessons from other industries, let alone other sports, about how to avoid human error in high-pressure decision-making. They thought they knew best. They were — hopelessly, comically — wrong."

I completely agree, the equivalent VAR processes in both Rugby and Cricket are much simpler, effective and transparent to the fans of their respective sports, it's seem incredible that football has managed to get this so far wrong.

The other parallel to me, is that the Premier League has got fixated on a single human error, rather than the leadership standing up and saying "we designed a poor process" which allowed a single error to escalate into a significant failing".  It reminds me of both the VW dieselgate process, where only one engineer was initially charged, and the Equifax data breach where again one engineer was blamed for not correctly scanning for a vulnerability.  In both cases, there were individual failings, but both were wider process failings.

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Krups XN250 Nespresso coffee machine repair

 This is the second time I've had to fix my Krups Nespresso machine, but as it's about a 20 minute job and the part costs about £5, that's fine with me.

The symptoms are that the machine appears to work fine, but the coffee is not dispensed into the cup, but down the back of the machine into the drip tray.  The video below gives a good detailed summary of what to do, but the guy in the video repairs the faulty part. In the UK the part is readily available on Amazon or Partmaster so I just bought a new one.  

As I mentioned above it's clearly a design fault as it's happened twice to me (maybe now I'm drinking more coffee at home due to much more WFH!), the part that breaks has two plastic lugs that over time must wear out and break.  Still a simple fix, the most annoying part is that Krups fit 'safety' Torx screws (about 1'20" into the video) which means it can be a pain to get the outer casing off. I'm managed to use a regular Torx screwdriver, but if you don't have one to hand and need to order one, make sure you get a safety one. 

In the era of iFixit, it seems naughty to me that vendors fit screws that are deliberately made more difficult for home repairers to deal with. I'm sure there's a lawyer somewhere saying, it's to avoid personal injury claims or some similar mealy mouthed excuse.  Anyway it's saved me twice, and is better for the planet.

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Ipad iMovie exports not completing - sound / speeded up clip fix

Random tip of the day. My daughter needed help exporting a movie from iMovie on her iPad.  Running iOS 15.4.1 and the current version of iMovie, her 3 minute movie wouldn't export.  We tried a couple of things, including trying to airdrop it to a MacBook Pro, but airdrop will try to export it then airdrop it so we had the same problem.

The problem was that the export would get to about 75% quite quickly, then slow down and never complete.  After a few Google searches and YouTube videos, we found the solution linked below.  For some reason there appears to be a bug in iMovie with any speeded up clips with sound.  My daughter had a clip that was speeded up, so as suggested in the YouTube video when I detached the sound and deleted it, the export worked fine.  Hopefully of use to others !

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Sabbatablog day 9 - dinner at Dell Quay

 Due to an excellent piece of poor organisation on my behalf - I'd tried to book to take my mum to dinner on her last night visiting us, but managed to get the date wrong ! (we ended up barbecuing at home), I had a spare dinner reservation at a local waterside pub - The Crown and Anchor at Dell Quay.  It's one of the few local places, that is on the water and gets the sun in the evening.

With the weather continuing to be excellent, we had a lovely evening in the sun, a cheeky pint and a burger with the family, the place was heaving but service and quality of food and drinks were excellent, highly recommended.  

Tip for the non-locals, book an outside table if the weather looks good, but a covered garden pod if the weather looks iffy, but note, these don't have a sea view/ in the sun.  The garden pods do get the inside (broader) menu, but the outside table have a slimmed down burger menu (with kids options).

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