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HEALTH internet Mobile Communications Science Technology Wearable Technology

Sweat-Powered Health Monitors? Whatever Next?

It was a very gloomy Sunday afternoon. It had been raining all day, and the wind was lashing the rain against the windows, through which I regarded my sodden garden.

Autumn was upon us, and I involuntarily shivered. We had just enjoyed a late lunch of warmed crusty bread rolls and Heinz’s cream of tomato soup, our go-to comfort food for afternoons such as this.

It was definitely a slobby Sunday, a day for curling up on the settee to enjoy a movie, or to catch up on the latest episodes of good TV shows.

We have currently been watching “Manifest” which appears to be a good show. Intriguing, and possibly quite plausible. I’m not sure where it’s going, but I will stick with it for the time being.

I picked up the remote and brought the TV to life. I was rewarded with a new advert for EE, one of the UK’s cellular networks. In this one, Kevin Bacon was promoting EE’s new 5G service.

In the advert, a barber was shaving a man’s face from a remote location.

To accomplish this, the barber, (located in Clapton in London, 250 miles away) was wearing a modified glove that was fitted with finger and wrist position sensors.

The man to be shaved, actor, Tom Ellis, was located on the top of Mount Snowdon in Wales, accompanied by a robotic arm, complete with articulated hand, capable of holding a shaving brush and a razor).

I was absolutley fascinated with this, watching as the barber, using a phone connected to the 5G network to see what he was doing, loaded a shaving brush with shaving soap, and then simultaneously saw the mechanical robot arm applying the soap to the man’s face, despite him being many miles away.

Subsequently, the barber picked up a cut-throat razor, and shaved the man’s face.

That’s a lot of trust, folks!

Now, I’m a bit of a sceptic, and am aware of how good CGI is, but it does link into my interest in the medical uses of 5G, so I decided to do some research.

My first port of call was the EE website, to see what they had to say about their latest campaign.

I was a bit blown away to discover that this was a REAL demonstration, and made no use of CGI, but instead used the EE 5G network and a custom-made robot arm.

Only recently, the world’s first (allegedly – you may know differently!) successful surgical procedure performed from a remote location was conducted in south east China, using the local Huawei 5G network.

5G is certainly going to change the way we live, but more about that in a later article.


The reason that I mention 5G here, is that it will no doubt have other uses in medicine and personal health care, especially when used in conjunction with wearable technology.

A few years ago, I carried a little more (lot more) weight than I do now, and my blood pressure was all over the place. As an incipient hypochondriac, I also suffer from a condition known as “White Coat Hypertension”.

I first discovered that I had this condition was at the renewal of my first Class 1 flying medical. My normally placid, mildly elevated blood pressure launched to positively near-death levels as soon as I sat on the chair in front of the medic.

Over the years, my blood pressure has been brought under control, and is consistently textbook normal.

Until I am having a flight medical. Then it’s at stratospheric levels again.

One of my doctors decided that I would need to undertake an ambulatory blood pressure check. This involved me wearing a bulky blood pressure monitor, complete with inflatable arm cuff, for a twenty-four-hour period.

During this time, the system would take recordings every ten minutes or so. I spent a miserable 24 hours walking round like Quasimodo.

At the end of the test, I was diagnosed with mild hypertension and was prescribed medication to deal with it.

Medical technology has advanced a lot since the early 1990s and now health monitoring systems have become a lot smaller and a bit more refined, but they still require a battery to power them.

However, digital wearable technology is now commonplace. Smart watches such as the Apple, Garmin and Fitbit models, which monitor many health factors including heartrate, blood pressure, blood oxygen levels, sleep tracking, electro-cardiogram (ECG) and physical activity.

Apple Smart Watch 5 Image Courtesy Raralu444 under CCA-SA 4.0

As wonderful as they are, these smart wearables are still limited by their need to carry their own power source – normally a rechargeable Lithium-Ion battery.

There are now developments that make this unnecessary.

A group of bioengineers working at UCLA* Samueli School of Engineering have developed a flexible magnetoelastic generator, that creates electrical power from the natural movements of the human body.

The principle is simple. If you remember your schoolboy (and schoolgirl!) physics lessons, you will probably recall that the interaction between magnets generates an electrical current.

The generator consists of a matrix of tiny magnets, woven into a stretchy, silicone sheet. When the sheet is flexed, the movement of the magnets against each other generates an electrical current.

Flexible, Stretchable, Self-Powered, Waterproof, magneto-elastic generator. Image Credit Jun Chen, UCLA

The sheet is flexible and soft enough that it may be worn comfortably against the skin. Movement of the muscles will flex the sheet, causing power to be generated. It’s even sensitive enough to create power from the tiny movements caused by a human pulse.

Impervious to sweat, or water, the system is quite capable of generating sufficient electricity to power a self-contained heart monitor, sweat monitor or thermometer.

Another recent system is a sweat-powered artificial skin, developed by researchers at Caltech’s Department of Medical Engineering.

Sweat-Powered Electronic Skin Image Credit – Caltech

This alternative method is based upon a soft electronic skin, or “e-skin” made of flexible rubber, into which are embedded several sensors together with what may only be described as bio-fuel cells.

Human sweat contains high levels of the chemical Lactate, which is a normal by-product of any form of metabolic activity, for example, from the activity of muscles when the body is conducting physical activity.

The bio-fuel cells built into the e-skin, absorb the sweat, and in the process capture the Lactate, which combines with Oxygen to produce water and Pyruvate. During the process, the biofuel cells generate electrical power.

The amount of energy generated is sufficient to power all the sensors woven into the e-skin and additionally, a Bluetooth© transceiver, which enables the e-skin to transmit sensor data to any Bluetooth© enabled device.

This useful technology will allow the remote monitoring of blood glucose levels, hormone levels, cardiac activity, body temperature and neural activity.

The same scientific team at Caltech, (led by Wei Gau Assistant Professor of Medical Engineering at the Andrew and Peggy Cherng Department of Medical Engineering) have also developed a system that uses kinetic energy to generate power for biomedical sensors.

To put it simply, a thin skin is created using layers of Teflon, Polyamide and Copper. This is attached to the person’s skin.

A further layer of Polyamide and Copper is allowed to slide back and forth over the skin’s layers, and induces an electric current. In the prototype, the team stuck the Teflon/Polyamide/Copper layer to the subject’s torso, and the sliding layer was secured to their arm, so that natural movement would trigger the generation of current.

Triboelectric Generator Prototype. Image Credit Caltech

This is known as a “Triboelectric Generator”.

Most of us will have experienced this at some point, when we have walked across a synthetic carpet, whilst wearing synthetic clothing. We build up an electric charge, which can then discharge to earth – sometimes quite painfully!

Now, all these human-powered sensors are in early stages of development, but in due course, they will become part of the Internet of Things (IOT), and will be using 5G to send real-time medical data to your family doctor, your diabetic or cardiac specialist or medical consultant.

Maybe they will even send biomedical data to the emergency services should you get cut whilst going to the barbers!

Brave new world?

You decide.

Go Well.

*University of California Los Angeles

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Categories
Ecological education Electric Transport English Culture Environment Motoring Science shipping Technology Transport Vehicle Safety Vehicles

Do You REALLY Understand Your Car?

Traditionally, the predominantly male operators of any form of transport craft confer a female personality to their vehicles. Down at a south coast yachting marina recently, I heard a proud owner boasting to a friend, saying “She’s truly beautiful”.

Pilots, including me, refer to their aircraft as “She”. “She flies nicely”, or “She doesn’t like being thrown about”, “She needs a touch of power when rounding out to land”.

Who could argue that She is beautiful. Supermarine Spitfire showing her elegance. Image courtesy Airwolfhound under CCA SA 2.0

It’s the same with cars, and it’s common to hear people, including women, referring to their cars as “She”. Before I get angry comments from my lady readers – yes, I am aware that many women own male cars, some that I know even name them.

The tradition of referring to a vessel as “She” goes back to ancient times. Nowadays, people may consider that this is somehow sexist, and objectifies women.

I prefer to believe that it’s more fundamental than that. Our early mariners were a superstitious bunch, and believed that the ship in which they sailed would offer protection and guidance, in much the same way that a mother or goddess would.

I refer to my aircraft as a “She”, as in my eyes she is elegant, pleasing to the eye, and demands to be treated with respect.

Today, there appears to be another reason.

Now, be honest. How many of you chaps out there believe that you don’t understand the woman in your life? How many long-suffering ladies out there are stupefied with their blokes’ methods and logic?

I have been happily with SWMBO for over three decades, but there are times when I am truly and utterly baffled by her. I know for sure that she experiences the same sense of bewilderment with my behaviour.

You may be wondering where this is going, but stay with me, dear reader.

If, like me, you own and operate, say, a five-year-old car, it will be fitted with some basic driver assistance systems. My car has rear parking sensors and steerable headlights. That’s it. Nothing fancy. It has standard Cruise Control, and an anti-lock braking system, like the one fitted to my previous 2002 Skoda Octavia.

If you decide to invest in a new car today, be prepared to be a little baffled by its behaviour and systems. (New cars are definitely female!).

In a previous article, I mentioned the Automated Driver Assistance Systems (ADAS) that are fitted to modern vehicles.

It’s likely your new pride and joy will be fitted with Adaptive Cruise Control, Lane Keeping Assistance, Blind Spot Monitoring, Autonomous Emergency Braking, Collision Avoidance Systems, Driver Alertness Monitoring, 360º Cameras and Intelligent Parking Aids.

To make the best use of these systems, drivers need to fully understand how they operate.

A few months ago, I decided to evaluate electric cars. I arranged to test drive cars provided by three of the main manufacturers, Kia, Nissan and MG.

Now, bearing in mind that all the vehicles I tested were fitted with some sophisticated systems, you would have thought that a full tutorial or some guidance would be offered by the salesmen before they let me loose on the road in one of their expensive cars.

Not quite.

All the dealers involved were more than happy to show me the boot space, and the clever stowages and storage areas, and gave me a very brief explanation of how to interpret the instruments and how to use the infotainment system, but not one discussed any elements of the ADAS in any real detail at all.

Luckily, I had conducted quite a bit of prior research, so I had a reasonable idea of how to change the level of regenerative braking, and how to use the different driving modes. However, there were many systems that, whilst I knew they were there, I had no idea how to configure them.

I have several friends who have recently purchased new cars, and when picking up their new vehicles, each one received no real training on how to use the systems correctly and effectively.

I have considered this, and it seems that this presents a bigger problem than I initially thought.

After collecting their new car from the dealer, proud owners will drive their new vehicle home, and maybe they will find the time to sit and wade through the Driver’s Handbook or Owner’s Manual. The onus is very much on them to gain understanding of the plethora of safety systems that their car is now loaded with.

More mature drivers, such as myself, will fall back on our “What’s to learn” mentality. We have grown up with cars fitted with few safety systems – maybe embryonic energy absorbing crumple zones, and collapsible steering columns. This is flawed thinking!


We had relatively unsophisticated in-car entertainment – maybe a push button radio, or a radio cassette player if we were driving a more luxurious model. I can remember being delighted with the fact that my first company car was fitted with a proper heated rear window and a fitted rear wash/wipe system.

Our cars were so simple that we just picked up the use of what systems we had as we drove. I think my biggest challenge was remembering on which side of the steering column the indicator control was located. The first few days of driving was always entertaining, with me switching the wipers on before making a turn!

So, for drivers of my generation, it is possible that we have a degree of complacency about the new systems, and maybe we don’t bother to sit down and read the book. (I do, but then I’m a bit geeky, having been a flight technical instructor for the past two decades!).

That may not be a good attitude to have these days.

In my world of professional aviation, we frequently refer to human factors, and even have training sessions on how simply being human affects the way in which a pilot interacts with an aeroplane.

There is a lot of automation on a modern aircraft flight deck. Autopilot, Auto Throttles, Flight Control Computers, Flight Management Computers, Automated Anti-Collision Systems, Ground Proximity Warning Systems, and Electronic Checklists and Diagnostics.

All of these systems must be understood, reacted to correctly, and effectively managed by the flight crew.

Despite high levels of safety-related automation, there are still incidents involving the crew falling asleep in flight, and flying past their destination. We still hear of aircraft being landed at the wrong airfields.

The same human factors will come into play in our increasingly automated cars.

There have been numerous reports of Tesla cars being involved in colliding with emergency vehicles whilst the Autopilot was engaged.

Most definitely human factors incidents, as the drivers simply assumed that the car was infallible, and therefore mentally disengaged and stopped supervising the on-board equipment.

A study by Massachusetts Institute of Technology (MIT) clearly showed that once drivers had engaged the Autopilot (or Adaptive Cruise Control) their focus of attention changed, and they spent much longer looking inside their cars, than paying attention to the road ahead.

Sometimes, drivers disengage to the point of falling asleep!

See this video of a Tesla driver, cruising and snoozing!

As a result, Nissan, at least, has incorporated what it calls an Intelligent Driver Alertness System. This system monitors the driver’s inputs to the steering wheel, and, using algorithms, it can predict the onset of tiredness and inattention. As arousal levels reduce, the chances of an accident increase, so the system suggests taking a break.

Screenshot of the Arousal Monitor. Wish my car would invite me for a coffee…

When I learned to drive, before making any manoeuvre, the mantra was “Mirror, Signal, Manoeuvre”. That has become ingrained behaviour, reinforced with 44 years of driving and in the region of 1.1 million miles travelled.

Wow! I have never worked that out before.

As a result, before lane changing, I always throw a quick glance in the door mirror. I have also ridden motorcycles for many years, so I can’t get out of the habit of looking over my shoulder as well.

If all is clear, I change lanes. Lots of people don’t do this and I have had to brake heavily to avoid being sideswiped on several occasions.

Interestingly, the Blind Spot Monitoring (BSM) systems being fitted to cars now are really good. You may be lucky enough to drive such a car, and, in many cases, the door mirror contains an indicator that turns amber when another vehicle intrudes into the safety zone, and turn red if a collision would result in the driver changing lanes.

Another piece of research studied the rates of lane-changing accidents across 26 US States. It found that accidents causing an injury were reduced by 23% in vehicles fitted with BSM systems.

If every US vehicle in 2015 had been fitted with BSM, it is estimated that 50,000 accidents and 16,000 injuries could have been avoided!

The other aspect of Blind Spot Monitoring is that used when parking or reversing. Now, I use all three mirrors, even though my car has a rudimentary parking aid that sounds a tone with increasing frequency as I reverse closer to a solid object – including a person, although I have never tried this.

Now, a further study has shown that the drivers of cars fitted with rear view cameras and sensors do not look to the sides of their vehicle before commencing reversing manoeuvres

Surprisingly, the use of rear-view monitoring cameras only reduced accidents involving “reversing into or over something” (maybe a person??) by 17%.

Still, a 17% reduction, is better than no reduction at all.

So, it all boils down to training and gaining an understanding of the equipment fitted to our cars.

I decided to check what the UK Driving Syllabus includes for cars and light vans (Class B Vehicles).

What I found was of interest.

As the document is undated, but is on the government’s assets publishing service site, as at October 2021, I assume it is a current piece of guidance.

I quickly reviewed it, and found two main concerns.

Firstly, it only mentions one Automatic Driver Assistance System, and that is Cruise Control.

Secondly, it focuses totally on driving a fossil fuel-powered vehicle.

Not a single mention of electric cars.

I do understand that they haven’t been around for very long – I mean, the Nissan Leaf has only been on the road since 2010, and what’s eleven years when you are setting the standards for people to learn to drive?

Sarcasm aside, there must be a need to teach new generations of drivers about the features, advantages and benefits of their vehicle’s on-board safety systems.

Maybe they should also be teaching students about the limitations of both those very same on-board systems, and their limitations as a human being.

You decide…

Go Well.

Categories
Climate change Ecological Econonomy English Culture Environment local economy Poverty Relief Recycling Science Society

I Don’t Want to Eat My Vegetables is No Longer a Valid Excuse!

I leaned back in my chair with a feeling of contentment. SWMBO and I were sitting in the snug of one of our nearby village pubs, and I was now comfortably replete after noshing an exceptionally large Sunday Roast lunch. 

Ahhh. Sunday Lunch in a comfy local pub

This pub is renowned locally for its excellent food, well-kept ales, and quaint, comfy surroundings. The staff, all of whom were youngsters, were polite, attentive, and friendly.

Additionally, I had other reasons for using this pub. They have a policy of only using locally-sourced ingredients for all of their menu items. So, my roast beef was from a breeding butchery near Southampton, the vegetables were from a local farm, and the guest beers that I chose were from either the triple fff* brewery, based in Alton, or the Hepworth brewery in Pulborough, just across the county border in West Sussex. 

I am currently trying to persuade them to stock some of the really good ales made by the Firebird Brewery in Rudgwick, also in West Sussex.

I really like the idea of supporting local business, and helping to reduce my food miles, and my personal carbon footprint.

I was stuffed full. Yet the side dishes containing more vegetables and condiments and sauces were also still stuffed full, despite SWMBO and I laying into them with such gusto. I felt quite guilty about this, and knew that I was wasting perfectly good food. 

Not the Sunday Roast in question, but you get my point? Serving for one – plus sides!

In my rural area, the waste wouldn’t be quite such a problem, as some of it would probably go back into the farming system to be used as animal feed, but in towns and cities, this would all go straight into landfill.

I wondered to what extent we as a nation were wasting.

What I discovered was truly staggering.

In the UK alone, we waste approximately 10 million tonnes of perfectly useable food every year! Alarmingly, less than 1% of that is recycled in any meaningful way. 

Food – Just chucked into a skip, and left to rot before going to landfill

At the top of our “oh, just chuck it out” list was bread, with 900,000 tonnes wasted each year – that’s about 24 million slices that are sent to landfill. A lot of sandwiches, by anybody’s standard.

Add that to 5.8 million potatoes, and a huge volume of other vegetables and fruits, and it’s easy to see that we have a serious problem.

According to research conducted by the University of Edinburgh, about 33% of farm produce is wasted for aesthetic reasons. Supermarkets usually have contractual requirements for their vegetables and fruit, that specify minimum sizes, dimensions, weights, and appearance. 

This is driven by their perceptions on customer requirements, but, to be honest, the shape of my carrots, or a blemish on the skin of an apple aren’t overly high on my list of priorities. 


As a side issue, I have never once been canvassed for my opinions by any supermarket chain. 

Ever.

A third of all UK-grown, perfectly edible fruits and vegetables are rejected by our supermarket buyers for not meeting their specifications, and so they are wasted. They are probably just ploughed back into the land – and all this in a country where we now run food banks for those who are in desperate need.

This MUST change. The global food system produces about 25% – 30% of global greenhouse gases (GHGs), and agricultural supply chains use up to 70% of our freshwater reserves. Every tonne of food waste that goes to landfill sites will generate about 4.2 tonnes of GHGs. We must grow less and waste less.

But I digress. So, back to my sumptuous pub meal.

The hospitality industry wastes over a million tonnes of food because of providing over-generous portions. This is a tricky issue to address.

The corporate mindset seems to be that customer satisfaction is better served by plating up too large a portion and having some waste, rather than serving a portion that is perceived by the customer as being too small. 

Maybe a mental reset is required. The hospitality sector, pubs, bistros, restaurants etc., should start serving smaller portions, and tell customers that if they would like more side orders of vegetables and sauces, then they may ask for them free of charge.

So far, most that I have written is related to commercial food waste. Now have a think about the amount of food that you personally waste in your own homes.

For every 13 million tonnes of food waste generated, 7 million tonnes is wasted by people like you and I!

That is the equivalent of throwing away one full bag of groceries in every five bags with which you leave the supermarket!

Various initiatives have been set up by several charities, such as Feedback Global’s “The Pig Idea”, which attempts to change the law preventing waste food products from being fed to pigs. 

This law was originally passed to prevent contaminated edible waste from entering the food chain for pigs, which was thought to have caused an outbreak of Foot and Mouth disease. 

This was enshrined into EU law in 2002, but now that the UK has left federal Europe, it is possible for the UK Government to consider rescinding this law, subject to animal welfare standards being maintained to ensure the quality of any food waste to be fed to pigs.

Should this happen, the UK could simply revert to the centuries-old practice of feeding waste food to pigs.

A World War 2 Poster, urging the public to save food waste to feed pigs.

The food waste generated by the food manufacturing, catering and retail sectors (which would normally be destined for landfill) could potentially be reduced by about 2.5 million tonnes per year – a drop of 20%.

This is staggering!

The United Nations has stated that if all farmers globally were to feed their livestock on waste food and agricultural by-products, then enough grain could be liberated from the system to feed an estimated 3 billion people.

Supermarkets are also responsible for a lot of food waste at the opposite end of the process. Not only do they reject perfectly edible foodstuffs at the farm, but they also waste perfectly edible food that they over-order, and then just can’t sell!

We have all seen it. Yellow labels on food that is “out of date” being sold at heavy discounts. Like me, you have probably taken advantage of some low prices for food that is at the end of its shelf life.

Good Deals are often to be had, if you are willing to eat expiring food on the day you buy it!

Sadly, a lot of yellow-labelled goods remain unsold, and are therefore thrown into the skip (I have watched this happen at a local supermarket), destined for landfill somewhere.

This is a sad situation, especially as food poverty affects 8% of the UK population, some 5 million people.

To put this into perspective, my dear old Mum, who is in her nineties, volunteers at her local church, and as well as working in the café on a regular basis, she is also involved in the Church’s food bank. 

The food bank, like so many others, collects food and then distributes it to those who are in need. Having grown up during the Blitz, and the privations of rationing during World War Two (and afterwards – rationing didn’t end in the UK until July 1954) she hates waste of any kind, and always tries to live sustainably, well before such a word entered our vocabularies.

A Typical Weekly Ration for an Adult in 1940. 4 Ounces is 115 grams and 3 pints is about 1.7 litres

It still shocks her when she hears about waste of any kind, but she is a product of her generation, and some things are never forgotten.

There is hope though…

There are some wonderful charities that try to save food waste, and help those most in need of support.

Take The Felix Project. They collect surplus food, including vegetables, fruit, dairy produce, and meats, from food manufacturers, farms, supermarkets, and restaurants, and distribute it to those most in need. 

Then there is FareShare, which was started 27 years ago in 1994, as a joint venture between the UK Homeless charity, Crisis, and Sainsburys the supermarket chain.

Originally called Crisis FareShare, the charity collects and redistributes food to over 1,000 UK charities, and has partnerships with Tesco, Asda, and the Trussell Trust (which support the UK’s network of Food Banks). 

The “Feed People First” campaign that it ran in 2018 tried to ensure that it wouldn’t cost the food industry more to donate their surplus edible products to charities, than it would cost them to send it to landfill or animal feed manufacturers. 

By the end of 2018, the UK Government had committed to providing funding of £15 million to enable business to divert its surplus foodstuffs to charity.

Since it was started, FareShare has provided 236.8 million meals all of which were donated to people in need via a network of frontline charities. This resulted in savings to the voluntary sector (assuming they would have had to buy the same amount of food and drink) of about £180 million!

This is a fabulous achievement, but it still highlights a vast mismatch between food supply and demand – there is such a large surplus! It also shows that our society is broken in a sad way, when people living in a supposedly civilised country are suffering food poverty, despite our very generous welfare state.

They alone are responsible for saving tonnes of waste every year, whilst reducing human misery at the same time.

As climate change strengthens its grip on our world, we will have to make some serious changes. This is not only at a global and state level. This is also at local level.

I am not a great horticulturalist, and have little interest in growing things, but I think that in future more families will have to grow some of their own foods to reduce the need for intensive farming and food transportation. Maybe misshapen vegetables and blemished fruit will be more prevalent. 

In fact, Morrisons supermarkets have proven that even ugly produce is nutritious, edible, and has value.

Morrisons leads the way…

There is an alternative though, if, like me, you are a lousy gardener.

How about not only reducing waste for landfill, but also reducing GHGs, and saving money in the long run?

This is where a small, self-contained domestic biodigester plant comes into its own.

Biodigesters are designed to capture the methane given off by decomposing organic matter. 

A Typical Domestic Biodigester

For most people, organic matter would be food scraps including vegetables, fruit, meat, fish, dairy waste, cooking oils, pips, nuts, and bread.  Some folks may operate smallholdings, and may therefore benefit further by enabling a certain amount of manure from livestock to be used. 

For the truly environmentally-conscious, biogas lavatories are on the market that enable human waste to be processed as well. 

A Biodigester Toilet. Waste not Want not? https://www.homebiogas.com/product/bio-toilet-kit/

Biodigesters consist of a simple tank, which may be made of hard plastic, or out of very strong PVC sheeting. The waste organic products are simply placed into the tank, and within a short period of time, helpful, friendly bacteria will start breaking down the material.

There are two main by-products of the process. One is a good source of methane gas, and the other is liquid fertiliser.

The gas generation is simple, natural, and ecologically friendly, and the methane gas output may be used to operate a cooker. Once up and running, a typical biodigester will produce enough methane for two hours of cooking per day.

The slurry that may be drained off at the end of the process is full of nutrients that are essential for plant health, and are odourless and non-toxic.

I would add a word of caution here.  If you do decide to install a biogas lavatory, and use human waste, then you can’t use the by-product as fertiliser, and it must be treated as sewage and compliance with disposal regulations is essential. However, you can still tap off the methane!

So, maybe it’s time to buy less food, and to encourage our supermarkets to be less restrictive when specifying the acceptable standards for fruit, vegetables, and other produce.

Even reluctant gardeners should have a go. It’s possible to grow beans, peppers, potatoes and tomatoes in pots – even on a small balcony. Every little helps.

If you have a larger garden, maybe invest in a biodigester, and reduce your reliance on mains gas. You probably won’t generate enough gas to run your central heating, but you will be cutting down your GHG footprint.

I guess some of the answer lies in our own hands.

You decide.

Go Well…

Header Photograph – Surplus Tomatoes piled up to rot…

* Yes, It really is spelt that way!