Category: Environment

H2 is difficult

I mentioned Hydrogen as an option for aviation. The use of Hydrogen to either power jet engines or to power fuel cells to provide electricity is a real technical option. Although the person I was talking to was engaged in environmental work, they shrugged their shoulders when I mentioned Hydrogen. They were certainly not impressed by these possibilities despite our agreement on the urgent need for de-carbonisation.

I can understand why there’s a level of cynicisms. On my part, it’s like the X-Files[1]. Fox Mulder was the believer and Dana Scully the sceptic. Broadly, I want to believe.

Today’s, liquid fuels can be explosive in certain conditions. However, it takes a considerable effort to create the conditions whereby a devastating explosion can occur. The Boeing 747-100 that was Trans World Airlines Flight 800 (TWA 800)[2] exploded, broke up in the air and fell into the Atlantic Ocean in 1996. This was an example of a worst-case scenario. 230 people were lost in that fatal accident. Now, the ignition of a flammable fuel/air mixture in aircraft tanks is better prevented by design and operational procedures.

If Hydrogen is to be viable in civil aviation such hazardous conditions will be harder to prevent. A flammable hydrogen/air mixture can be ignited much more easily than conventional liquid fuels. Such dangerous situations can be prevented but the measure to do so will require robust design and stringent operational procedures.

Several development programmes are underway, making practical Hydrogen powered aircraft viable. A range of aircraft configurations are possible. From hybrid generator and electric motor set-ups to combustion-based propulsion. This work is moving from academic research into commercial possibilities.

There little read across between the behaviour of conventional hydrocarbon liquid fuels and liquid Hydrogen. This would be evident in any serious incident or accident scenario. Let us imagine the case of British Airways Flight 38, in 2006, a Boeing 777-236 that came down at the end of a runway at London Heathrow[3]. A significant amount of fuel leaked from the aircraft after it came to rest, but there was no fire. There were no fatalities.

The breakup of liquid Hydrogen tanks or plumbing in such a scenario would almost certainly result in a significant fire. The mitigating impact of that fire is the lightness of the gas. Instead of liquid fuel pooling on the ground, Hydrogen would burn upward. However, any explosion could be devastating.

So, for large aircraft design the provisions to protect liquid Hydrogen tanks and plumbing must be extensive and extremely robust. This would have to be maintained, as such throughout the whole operational life of the aircraft. These requirements would be onerous.

Keeping crew and passengers well away from Hydrogen infrastructure will be a must.

POST 1: Crashworthiness doesn’t get much of a look-in. Without it there’s going to be a problem over the horizon. https://www.ati.org.uk/flyzero-reports/

POST 2: At least for eVTOL aircraft some work is being done. https://ieeexplore.ieee.org/document/10011735

[1] https://www.imdb.com/title/tt0106179/

[2] https://www.history.com/news/twa-flight-800-crash-investigation

[3] https://assets.publishing.service.gov.uk/media/5422ec32e5274a13170000ed/S1-2008_G-YMMM.pdf

2053, not so far off

Language is marvellous. We have all sorts of ways of expressing ups and downs, goods and bads, dreams and realities. This week this slogan caught my eye: “Our third decade of climate action”. I didn’t know whether to be impressed or to think that’s a long time given how little we have achieved. I suppose both responses are off the mark. Neither should I be impressed or dismissive of what has been done in the last 30-years.

Now, “sustainability” is a word[1] that gets banded around like confetti. That certainly wasn’t the case in 1990. That’s not to say there wasn’t a green movement. Public awareness of the need to change was triggered in the 1970s. It’s only that what was a minority interest is now a mass interest.

If the multiple crises of the 1970s had motivated sustained change, then there’s no doubt we would be in a hugely better place than we are now. A great number of projects would have matured and alleviated the globes environmental burdens. New markets would have developed.

The observation I have is that rather than adopting the tough route of positive change, instead we took the easier path of going for the low-cost option. Oil and gas were as alluring as chocolate and sunny summer beaches. Does this tell us anything useful about human nature? Loads of memes scattered around social media would like us to think so. They are hardly profound. Mostly bland.

Language is marvellous. There’s a catalogue of famous speeches that mark moments in history when change happened. Or at least, times when many people pivoted from one position to another. Powerful words can transform.

Our problem in 2023 is that we are saturated with noise. Endless reassurances that big organisations pump out tell us how well we are doing. Brave politicians implore us to move in a different direction. Campaign groups thrust “in-your-face” activist at us. Sadly, the collective effort is culminating in many people switching off. There’s the real danger that the next 30-years will experience a sluggish movement and even a dumb reversion to past practices[2]. It’s a prospect that hovering in plain sight.

Language is marvellous. What we need, at this moment in history, is not more words but some truly meaningful words that motivate real change. Future generations, and it’s unlikely that I’ll be here after the next three decades, but not impossible, must not be left with an enormous mess brought on by our reluctance to change. Oil and gas are not the future. We must not put off the day we wean ourselves off these two.

[1] https://www.un.org/en/academic-impact/sustainability

[2] https://www.gov.uk/government/news/hundreds-of-new-north-sea-oil-and-gas-licences-to-boost-british-energy-independence-and-grow-the-economy-31-july-2023

Local air

There are cases of synergy. That’s where aviation and local authorities have a mutual interest. This often centres around the economic prosperity of an area. Relationships can be complex, difficult, and fraught with volatility. There are plenty of housing and industrial estates that cover the ground of former airfields. Like the railways that closed under Beeching’s axe[1].

Public interest was dominant 50-years ago, but privatisation dramatically changed relationships. Sustaining profitability through good times and bad have proven to be more than some locations could support. There’s so many combinations and permutations but fewer and fewer active commercial airfields in the UK.

London Manston Airport is an airport that only just clings on to existence. In 2013, the Welsh Government acquired Cardiff Airport. So, some aviation facilities have returned to public ownership and run as an arm’s length business. A few airports are given support to ensure connections exists between remote parts of the UK. Highlands and Islands Airports is an example.

Advanced Air Mobility (AAM) is coming. This is the extensive use of electric vertical take-off and landing aircraft (eVTOLs). AAM is an innovative concept that will require Vertiports and integration into busy airspace. To make the economics work a lot of routes will be in, and over urban areas.

My view is that AAM will only succeed in the UK if aviation and local authorities come together and embrace it. That is going to be a massive challenge whatever national government does.

In the case of local authorities with a mission of protecting the interests of residents this has often meant objecting to aviation developments. I go back to proposals of 30-years ago to make Redhill Aerodrome a feeder to London Gatwick Airport[2]. This was well and truly shot down by local interests. In fact, rightly so given the complex twists and turns it would have made in the airspace.

AAM needs the harmonisation of standards to ensure interoperability anywhere in the country. There are one or two UK local authorities that are already embracing the potential opportunities of this new form of flying. Coventry City Council is taking on the challenge[3]. It’s welcoming the development of the ground infrastructure for “air taxis” and delivery drones.

By the way, my view is that introducing the subject as “flying cars” or “air taxis” is not a good idea. This creates images from science fiction that may not resemble the reality of these new air services.

[1] https://www.networkrail.co.uk/who-we-are/our-history/making-the-connection/dr-beechings-axe/

[2]https://john-w-vincent.com/wp-content/uploads/2023/08/bf3ec-clear_for_take_off.pdf

[3] https://www.coventry.gov.uk/news/article/4232/world-first-hub-for-flying-taxis-air-one-opens-in-coventry-uk-heralding-a-new-age-of-zero-emission-transport

ULEZ

Londoners in all Boroughs need clearer air to breathe

Oh yes. London has an air quality problem. It’s not the only city by any means. My recent trip to Cologne left me in no doubt that cities must address this problem. It’s an insidious hazard. It’s not so – in your face – as noise or water pollution. We’ve this human capacity to normalise bad things. Much to our detriment. Air quality becomes most evident when you move from a place of bad air quality to a place of good air quality. Then the difference becomes acutely noticeable.

Last weekend, I was in the West Country. Way down the A303. The difference is quite striking.

Last evening, I was traveling on the Tube to get to the Albert Hall. The difference is quite striking.

Whatever you may think about the implementation of the Ultra Low Emission Zone (ULEZ) in London, there’s a need to do something drastic.

Expanding ULEZ across all London Boroughs from 29 August 2023 is getting a lot of political attention. No doubt some of this is whipped up purely to punish the Labour Mayor. However, the dilemma is clear. Penalising a lot of people who are not directly feeling the discomfort of poor air quality is inevitably going to cause a stink.

Now, we shouldn’t get disproportionately agitated. That fact is that poor air quality is killing people is not in question. The fact that a small fraction of vehicle owners will be made to pay is not in question[1]. The balancing act between reliving an unacceptable situation of harm and causing minimal economic pain is a tricky one. It would be a tricky one for whoever was in power.

My view is that measure that force people to change their vehicles should be accompanied with a practical scheme to compensate them for significant financial losses. Or that the emissions thresholds set should take account of the natural turn-over of vehicles that takes place in normal years. The political controversy of the moment is much because of the speed of change and its coincidence with a cost-of-living crisis that is very real.

Londoners in all Boroughs need clearer air to breathe. But London doesn’t sit in isolation. Afterall the Borough boundaries do not track urban boundaries. Parts of adjoining areas are equally urbanised, and the air doesn’t know about administrative boundaries. The M25 motorway doesn’t do much for air quality, that’s for sure. So, hearing of the London Mayor doing battle with adjoining areas is a bit sad. Solutions need to be negotiated with all impacted parties regardless of the politics.

By the way, I’m not impressed with communications from Transport for London. I clicked on an e-mail sent to me on the above subject and this came up: “This link has expired. Please contact the sender of the email for more information.” Thanks a lot.

[1] More than 4 out of 5 vehicles meet emissions standards, but if you use a petrol vehicle over 16 years old, or a diesel vehicle over 6 years old, you need to check it.

Energy Policy

Saint Augustine’s early life was not what we associate with a saint. As a young man he prayed “Lord, make me chaste (pure) – but not yet!” Just now that’s the way, I fear, we are thinking of the environment. Global, national, or local. It’s total human but it needs to be fully recognised for its downside. Yes, we would like to do more to restore our environment and fight climate change but we’d rather it happened tomorrow. Tomorrow, tomorrow.

The instinctive urge to put-off decisions for what appears to be an easier life now rattles down through history. The lesson we might learn is that this approach is generally a bad way of going about thing if long-term success is the aim. Civilizations have ended because they failed to change.

This blinkered approach could be called political expediency. It’s at the core of what has become political populism[1]. The drive to persuade an electorate by retreating from commitments and heralding jam today. This fits our social media saturated public debate to the tee. I want it, and I want it now. The future will look after itself.

It’s a sad philosophy. I say that because the premises is that we may as well live well today because we have no control over what happens next. In populist terms, that’s put down to an imaginary conspiring elite that will inevitably win regardless of what you do. Truly nonsense.

That might have been true in the stone age but its far from true in the 21st Century. In reality, and on average, individual citizens have more choice than they have ever had. I say “on average” because there’s a billion people in the world who still live on the breadline.

Anyway, my point is that putting-off environmental measure is foolish. I’m reacting to a Conservative Energy Minister, has said that the UK government will “max out” remaining reserves of North Sea oil and gas[2]. I’s almost as if the Minister thinks this has no impact. That’s other than short-term political gain amongst climate sceptics and right-wing newspaper owners.

If the target for Net Zero is – yes but not yet – there’s virtually no hope of achieving the goal. Events being what they are there will never be a perfect time to stop using fossil fuels. I’m in agreement that the rundown of fossil fuel use should be graduated. However, putting off real change doesn’t make change easier. In fact, it makes change harder.

In the run-up to a UK General Election the possibilities for policies of self-harm are all too evident. A Conservative Government desperate to cling on to power will wriggle and produce contorted justifications for delay. It’s a basic instinct.

I’m not saying that we should all become zealous exponent of hairshirt policies. What is desperate is that we don’t become side-tracked from practical measures that can be practically taken. Taken now.

Work as though everything depended on you, and the choices you make. That needs to be true of Government Ministers as much as every one of us[3].

[1] https://www.thoughtco.com/populism-definition-and-examples-4121051

[2] https://www.ft.com/content/407b834e-a503-4de9-acab-fcf88d76dbb3

[3] Pray as though everything depended on God. Work as though everything depended on you. Saint Augustine

Short-sighted

None of that comes cheap.

OK. Why are mini-nuclear power stations such an irrational idea? The industry is selling these untried, untested power station as completely unlike that which has gone before. A Conservative Minister has been echoing their marketing brochures.

Let me say, with power generation there are some basic realities that remain the same.

Fuel must be transported to power stations and waste must be removed from them on a regular basis. For coal, that was the reason for the sitting of large power stations in the past. For gas, there was more flexibility in location, but the costs of transportation still needed to be minimised. For such innovations as waste-to-energy plants, proximity to the source of waste presented a major problem. Neighbourhoods rarely invited these plants to be built close by.

Spreading the distribution of nuclear fuel and waste around the country doesn’t sound like a good idea to me. Cost of transportation are high. Safety is paramount. Security is always a grave concern.

Now, I understand the need for limited numbers large-scale nuclear power stations. They provide a reliable base load when the renewable sources of power are not available. The wind doesn’t blow.

Although, there are a variety of different international companies in the nuclear business the notion of a “free market” in the conventional sense is not a real prospect. The investments needed to be competent and meet regulatory requirements in the nuclear business are huge. Projects are there for the long-term. A whole working career of a nuclear engineer may be locked to one technology.

Experience has shown us that a goal of zero accidents rarely delivers a reality of zero accidents. These are complex engineered systems. It doesn’t matter if they are big or small the complexities remain. Yes, safety can be managed in a safety critical industry but there had better be preparedness for worst possible outcomes[1]. With these nuclear plants decommissioning and recovery from significant incidents of contamination must be accounted for in any design, implementation, and operation. None of that comes cheap.

Overall, in Britain there are much better paths to travel than the mini-nuclear one.

It absolutely astonishes me that, given the enormous tidal range of the Severn Estuary[2] we have never captured the energy of those waters. Equality in a nation, with a coast as large as ours, we have only ever dabbled in wave power[3]. Let’s have some genuine innovation. Let’s think like the Victorians and build for the long-term.

Why are we so incredibly short-sighted in Britain?

[1] https://www.bbc.co.uk/news/world-13047267

[2] https://en.wikipedia.org/wiki/Severn_Barrage

[3] https://en.wikipedia.org/wiki/Salter%27s_duck

Bad Smell

Where is the accountability?

My desk, that’s the one in the early 1990s, faced towards the London Gatwick airport approach. It was a good reminder of the business we were in at the time. Seeing aircraft land and take-off about 500 m from the sheet glass windows of our office block was the daily background. Being in a rugged hermetically sealed building aircraft noise wasn’t a great concern.

Little more than 300m from the building and looking in the same direction was, and still is, the Gatwick sewage works. Its structures were low rise, so it was often hidden behind the greenery. Every so often, a strong wind would blow from the northeast. When it did a distinct odor filled the air. Yes, you guessed it. The sweet smell of the sewerage works would permeate the air conditioning.

This odor was at its most notable in the metrological conditions called an inversion[1]. In fact, given the seasonal frequency of these weather conditions it could be said that Gatwick wasn’t the most sensible place to build a major airport. These occasional pongs were a bit of a joke. Along with the occasional smells of unburnt aviation fuel it was just life at the airport. Lingering odors didn’t stay for long. A day at most and the wind would change direction back to where it normally came from – the south west.

Airports and sewage works are not a good combination for the health of rivers and streams. Long ago, when Gatwick airport was built the tributaries of the River Mole[2] were diverted. The part of that river, the Gatwick stream going north to south, at the end of the runway, is an unattractive V-shaped gully. Not nice for nature at all. There was a track that ran parallel with the river. In the summer, I’d walk that track at a lunchtime as it was a way of getting to the airport’s south terminal.

In the news, Thames Water are being fined for dumping raw sewage in the River Mole[3]. The consequences of the UK’s water regulator[4] taking a relatively hands-off approach to managing water companies, since privatisation in the late 1980s, has come home to roost.

I must admit, I’m not the least bit surprised. So far, the dance of those who shrug their shoulders astonishing. Ministers, regulators, company chiefs are all pointing fingers at each other.

The sequence of events is mind blowing when looked at over several decades[5]. Chief executives attracting massive salaries. Companies being loaded up with debt. Generous payouts to shareholders. Investments in infrastructure not keeping pace.

Ofwat, the regulator talks with incredible complacency. Such weak regulators are no more than a piggy in the middle as the powerful forces of unethical commercial behaviour and disinterested government oversight combine. As millions of families struggle with the cost of living this kind of failure is intolerable. Where is the accountability?

[1] https://www.metoffice.gov.uk/weather/learn-about/weather/types-of-weather/temperature/temperature-inversion

[2] https://www.southeastriverstrust.org/river-mole/

[3] https://www.independent.co.uk/news/uk/crime/thames-water-sewage-spill-gatwick-airport-b2368707.html

[4] https://www.ofwat.gov.uk/

[5] https://www.bbc.com/news/business-66103356.amp

Glasto 2

The weekend music city in the land of the summer people has had a vintage year. Normally, west country fields are covered in lush green grass. One of the most rugged plants on the planet. With the blue sky, overhead sun, and hundreds of thousands of feet, the green of Worthy Farm hides in the hedgerows. The land has browned in the heat. Music filled the air. Sound was everywhere. Now, thousands of revellers belong to a family of festival goers who want to do the whole thing over again, and again.

Yes, I know there’s a lot that’s mainstream. It’s probably an anathema to anyone under the age of 20. Looking at the audiences, a man over-60, like me, wouldn’t have felt out of place. Especially watching The Pretenders[1] Saturday night session. Which was excellent, by the way.

Watching the festival from afar, BBC Music has excelled with its coverage of this mega outdoor event. They curated material from the thousands of acts, catering for a good selection of tastes. Rick Astley and indie band Blossoms performing songs from The Smiths was a sight to see. The “Never Gonna Give You Up” 80s star crossed over to do a bang up job. Astley playing drums while thundering out the AC/DC anthem “Highway to Hell” – don’t tell me there’s nothing weird about Glastonbury.

What we got to see was a snap. New artists took to stages across the site. Some tried, some failed, some won and others are better for the exposure. Viewers of the box, like me, got only a small a window on the Glastonbury world.

On my last visit to Glastonbury, a couple of months ago, I sat in a tea shop with my mum. The town is an amalgam of the ancient and modern. The counterculture of the shops selling healing crystals mixes with the Abbey[2] and cake shops. I was remembering it as a child going to Glastonbury cattle market[3] with my granddad. It was to sell pigs, hobnob with local farmers and do a bit of shopping. He had a small box trailer which he towed up and down the Somerset hills on-behind a lovingly polished Mk III Humber Sceptre[4]. The heady blend of mystical traditions and local history makes Glastonbury a unique place. Its landmarks stand out picture postcard.

Last night, Elton John played a magical set. In perfect weather, in a perfect setting he pulled out all the stops. Had he awakened from his long slumber, King Arthur would have been dancing. Elton’s performance was legendary.

Elton gives a steping stone to new artists. Lifting up the next generation adds to his huge legacy. Songs that span the decades rang out over the hills. On my small screen, in the living room those fields looked like the best place to be for any festival goer this year. Glastonbury festival’s status as a foremost event in British culture is sealed.

[1] https://www.rollingstone.com/music/music-features/chrissie-hynde-pretenders-new-album-1029689/

[2] https://www.glastonburyabbey.com/

[3] https://www.glastonburyantiquarians.org/site/index.php?page_id=175

[4] https://en.wikipedia.org/wiki/Humber_Sceptre

Weight

Projects aiming to electrify aviation are numerous. This is one strand to the vigorous effort to reduce the environmental impact of civil aviation. Clearly, feasible aircraft that do not use combustion are an attractive possibility. This step shows signs of being practical for the smaller sizes of aircraft.

Along the research road there are several hurdles that need to be overcome. One centres around the source of airborne power that is used. State-of-the-art battery technology is heavy. The combinations of materials used, and the modest power densities available result in the need for bulky batteries.

For any vehicle based on electric propulsion a chief challenge is not only to carry a useful load but to carry its own power source. These issues are evident in the introduction of electric road vehicles. They are by no means insurmountable, but they are quite different from conventional combustion engineered vehicles.

The density of conventional liquid fuels means that we get a big bang for your buck[1]. Not only that but as a flight progresses so the weight of fuel to be carried by an aircraft reduces. That’s two major pluses for kerosene. The major negative remains the environmental impact of its use.

Both electricity and conventional liquid fuels have a huge plus. The ground infrastructure needed to move them from A to B is well understood and not onerously expensive. It’s no good considering an aircraft design entirely in isolation. Any useful vehicle needs to be able to be re-powered easily, not too frequently and without breaking the bank[2].

Back to the subject of weight. It really is a number one concern. I recall a certain large helicopter design were the effort put into weight reduction was considerable. Design engineers were rushing around trying to shave-off even a tiny fraction of weight from every bit of kit. At one stage it was mooted that designers should remove all the handles from the avionics boxes in the e-bay of the aircraft. That was dismissed after further thought about how that idea would impact aircraft maintenance. However, suppliers were urged think again about equipment handling.

This extensive exercise happened because less aircraft weight equated to more aircraft payload. That simple equation was a massive commercial driver. It could be the difference between being competitive in the marketplace or being overtaken by others.

Aviation will always face this problem. Aircraft design is sensitive to weight. Not only does this mean maximum power at minimum weight, but this mean that what power that is available must be used in the most efficient manner possible.

So, is there a huge international investment in power electronics for aviation? Yes, it does come down to semiconductors. Now, there’s a lot of piggybacking[3] from the automotive industries. In my view that’s NOT good enough. [Sorry, about the idiom overload].

[1] https://dictionary.cambridge.org/dictionary/english/bang-for-the-buck

[2] https://dictionary.cambridge.org/dictionary/english/break-the-bank

[3] https://dictionary.cambridge.org/dictionary/english/piggybacking

Sound in Water

We are all used to what light does around us. For the most part light travels in straight lines. I see you because of the light reflected off you. With our stereoscopic vision, I can estimate how far away you are from me. So, humans are equipped to detect range and direction. That’s incredibly useful in everyday life. We’ve evolved with a good ability to sense of our local environment.

We have two ears. So, to a degree we can judge the direction a sound is coming from in the air. That does get more complicated as the wind blows, with reflections and other noises clutter up our environment. How far away something is presents us with guess work. In the dark, a loud person close to us isn’t too difficult to guess. A quest person, far away is much more difficult to guess.

Sound in water behaves with some of these characteristics but temperature has a significant impact.

Our human experience of sound in water isn’t all that good. That’s down to the interface between air and water. For us water is not our natural environment. Our ears are attuned to sounds in the air.

There’s a device called an expendable bathythermograph (XBT). A nice title that makes this device sound high-tech and whizzy. The truth is that it’s remarkably simple. It’s a thermocouple, for measuring temperature at the end of a long wire that uncoils as it descends in water.

Thrown overboard at sea, the XBT sinks. At the surface a chart is drawn of the temperature profile of that point in the sea. Knowing the temperature profile, it’s possible to calculate what the sounds will do in that seawater. There are variations in the speed of sound in water with temperature.

Key factors to consider with the propagation of sound in water is pressure and temperature. Depth and pressure are simply related. Salinity has an impact too but that’s not the major factor at greater depths. At the deepest point in the sea the temperature is relatively constant.

A student project of mine was to design a sound velocity meter for use in the sea. The idea was to directly measure the speed of sound in water. It was what’s called a “sing‐around velocimeter.[1]”

What all this amounts to is that sound may not travel in a straight line in sea water. So, if a sensor on a surface boat picks-up a sound it may not be so easy to say where it’s coming from without a lot of additional information.

Those searching for the missing submersible in the North Atlantic are aware of the tricks that sound can play in seawater. Let’s hope that the sounds that have been reported as being detected prove to be useful in finding those in peril.

[1] https://pubs.aip.org/asa/jasa/article/85/S1/S112/649512/Measurement-of-the-sound-speed-in-air-by-sing