An ancient supermaterial

That’s what hemp is – a supermaterial that has been uses since ancient times. Perhaps you already knew about the textile uses of the material, the possibility of making paper, rope, sails, clothes and even shoes from the fibre. But that is just a small part of the many, many uses for hemp. And today new exciting possibilities are still being added.

Hemp for industrial uses comes from the same Cannabis Sativa plant as the one with drug use, but in this case the strains that contain hardly any psychoactive substances are selected, though even so it’s usage is not legal in some countries.  It is one of the most fast-growing plants in existence, and was spun into fibre for the first time some 50,000 years ago.

Hemp seeds can be eaten as they are, they are a common ingredient in granola, or turned into flour or sprouts. The seeds can also be pressed into oil, used in cooking, cosmetics or for making plastics or even biofuels.

More recently hemp has been finding new areas of application in the construction industry as fibre boards, building blocks and thermal and acoustical insulation. Test are being conducted to create building panels based on a mixture of hemp fibre and lime. These panels are being designed to be rapid to install, with optimal hygrothermal performance to create energy and resource-efficient buildings.

Today new scientific experiments is being done with the inner bast fibres of the hemp plant, a part that is normally not used today, but left for landfill. These “waste” fibres can turned into nanosheets and used as supercapacitors for the new energy-storing devices of the future.  Existing batteries are slow to charge and to discharge, while supercapacitors can discharge all their load very rapidly . This makes them ideal as battery storage for electric cars as they will also be much quicker to charge.

Normally supercapacitors are made with graphene, which is very expensive to produce. Now using leftovers from hemp production, a perhaps even better material can be made, for just a small fraction of the cost.

Storing the sun / Almacenando sol

The amount of solar energy that reaches Earth’s surface is enormous and is naturally one of the main reasons why this is a habitable place for humanity. Because the planet is round the surface receives the solar rays at different angles at different locations. As the Earth’s axis towards the sun is tilted by 23.5°, places further away from the equator receive more solar energy in some parts of the year than others. At the latitude of 40° (like for example in Madrid) the surface receives three times as much radiation in June than in December.

The lower the angle, the further the radiation has to travel through the atmosphere, and the less of it is left when it reaches the surface. So at the poles the angles are so low that very little energy gets through, and in wintertime there are long periods without light.

The suns elliptical course around the sun during year (it is closer to sun when it is summer in the southern hemisphere) does not amount to enough difference for making the southern hemisphere hotter than the northern during their respective summer periods, as this difference is mostly absorbed by the oceans.

When we use fossil fuel we are really using the energy from the sun that reached us millions of years ago. That energy was first stored in organic form, like for example plants, by a process of photosynthesis and then decomposed deep below the surface into energy forms like coal, oil or gas. That process is still going on, but is so slow and our outtake of fossil fuels so vast that it can’t be considered a renewable energy source.

The problem with not having the same amount of solar energy all the time is that you would want to store the received energy on a sunny summer day and keep it for a cold winter night, which is of course much easier said than done. First you would need a very big storage capacity (which is expensive) to able to retain enough energy for when you need it and can’t get it and, secondly that storage should be absolutely stable so that what you captured is not slowly leaking away.

A very interesting on-going research project at the University of Chalmers in Sweden is trying to use chemical solar capture with the help of an artificial molecule (made up of carbon, hydrogen and nitrogen) as a way of creating a durable energy storage. This molecule has different forms (isomers) with different energy levels and when it is exposed to sunlight in a solar collector it changes from a low-energy form to a higher energy form, storing the energy inside its chemical bindings.

The molecule can then be stored for up to 18 years without loosing it’s new form and when the energy is needed the liquid containing the molecules is passed through a catalyser, where heat is produced and the molecules turn back to their original form. The good thing is that the system works as a closed circuit as the molecular liquid can be passed through the solar collector again and again to store new energy.

Aeroponics

Aeroponic farming is growing plants in air without any substrate or other growing medium. The plants are sustained in place and their roots are sprayed with a  “mist” to provide them with the necessary nutrients. The support enters in minimal contact with the plant holding it at the stem with the leaves and crown growing above and the roots hanging free in the air below. If the environment is kept free from pathologies the plants can grow quicker and healthier than they do in soil as the roots are better oxygenated having direct contact with the air.

There are many cases in nature where plants grow like this with air roots under humid conditions, for example orchids have a natural tendency of aerial roots and cling onto other plants and get their nutrients from them. Recent research has shown that a great number of plants can be used to grow in this way and not only the ones with a natural tendency for it.

Potato plants are grown using aeroponics as a means of getting more and same-sized tubers for planting. The method improves productivity as one plant hanging in the air yields up to 20 small potatoes instead of 3 or 4 for with the traditional soil-based method. The roots are normally kept in darkness but are accessible and can easily be harvested in the right moment without moving the plant. The method saves water, not because an aeroponic plant need less of of it, but because all excess water is recycled back to the plants again.

One part of the ongoing preparations and investigation for future space travel to planet Mars is looking into aeroponic growing as part of the survival strategies. The red planet has very adverse conditions indeed with the highest temperatures around -25 °C and the lowest below  -100°C and very little water, why growing plants naturally seems out of the question. In one experiment at the Czech University of Life Sciences, the scientists are experimentally growing lettuce, mustard, radishes and herbs using aeroponics, proving that they can survive almost without water.

On the Spanish island of Ibiza one of the first vertical gardens in Europe using aeroponic towers to grow food naturally while saving 95% water in comparison to conventional organic farming. Besides saving water the method also save space and improves crop yields. The tower structures have a separate slot for every plant where the mineral bases nutrients are circulated internally. A great variety of plants are being grown, like tomatoes, cabbage, lettuce and even melons.

Critics to aeroponics argue that, as the plants are fed with artificial nutrients, they don’t have access to the microbiology of healthy soil. In that sense aeroponic farming can be compared to feeding humans directly through an intravenous solution. In that sense, the role of soil is as important as the role of the stomach, to break down organic matter and provide micronutrients and other things that are associated with organic food production. Still, if we want to make a living in such a hostile environment as the red planet, the method seems rather promising.

 

Preppers & Survivalists

What do you think will happen when a really big crisis occurs? Like for example extreme weather situations, pandemics, environmental disaster, a major supply shortage or some kind of conflict or unrest that gravely affect the normal societal functions. Will the society be able to cope with extreme stress situations, and care for the citizens needs, or will it break down and leave everyone having to rely completely on their selves.

Preppers are the ones that have decided that they can’t just rely on society for taking care of the crisis management for them, but that they will have to prepare (”prep”) for those situations themselves. So preppers stockpile food and water in their homes, and normally go around with a small bag, like an urgency kit, full of a lot of useful tools for when “the shit hits the fan” (when everything goes wrong) as they tend to call it.

They also prepare their homes to be safe, resilient and defendable strongholds and rely on backup plans to be able to sneak away safely to another and more durable location when the situation around them seems to be too unstable.

While some people just prepare to endure a threatening situation, hoarding up provisions, practical utensils and an escape route from it all to a safe haven, others, the survivalists, have decided they must be ready for maintaining themselves for a much longer time period, since all stored provisions will in the end be finished if you can’t produce new ones yourself.

So being a survivalist, you would want to secure your own stable food production, collecting rainwater, growing food on land or in water, raising hen, fish and smaller animals to maintain a constant flow of nutrition. Another issue is having access to energy for cooking and keeping warm without an electrical grid or fossil fuels to provide that service, using durable energy resources like the sun, wind of perhaps just having access to enough fire wood.

Most survivalists prefer a discrete hide-away place in a rural context with enough space to be self-sufficient; yet others some have created a complete ecosystem in their urban backyard to able to generate enough food and energy.

While preppers and survivalists often are looked upon by others as raving mad bunker builders and hoarders, waiting forever for the soon-to-come doomsday, those people see the rest of the world as naïve fools that will just panic and not last a day without water and electricity.

In the end it seems a bit like the classic tale about the ant and the grasshopper, where some work hard all day to prepare for an uncertain future while others go happily about their life unknowing about the perils to come. I do agree on that, even if you can find rather extreme examples of people that have become obsessed with storing stuff, doing weapon drills and planning for a complete breakdown of the world as we know it, realizing just how fragile our society really can be, is rather healthy.