Flights of Fancy – Part 3

This series is an extended musing on what might happen with a really robust solar energy industry that, instead of trying to outcompete all of the other electricity providers, using the relatively low-cost energy, both heat and electricity, to create a product that otherwise is relegated to irrelevence because of scarcity – carbon nanotubes and nanowires.

I discussed blimps – airships without internal structure – as an application of carbon-nanofabrics, because of their great strength and light weight.

In this part, I will briefly explore the uses of carbon-nanomaterials in the construction of balloons and tethers. Like blimps, a super-light, super-strong fabric can create a balloon that can be bigger than those currently employed as weather balloons, which loft very high in the atmosphere.

Currently, balloons are not used much because they lose helium (which is expensive) and fall back to earth, and they could be at their most useful very high in the sky, which means that they cannot be easily tethered to the ground, because the tether, if made with steel cables, would be so heavy it would drag any balloon made of conventional materials back down to the ground.
A carbon-nanofabric balloon, filled with stronger-lifting hydrogen, could be very large. Large enough to support several key pieces of infrastructure – a moisture-capture mechanism of some kind, a suite of photovoltaics and you have a hydrogen-generating plant. This way, as the pressure drops as hydrogen is lost through the balloon’s membrane, it can be replenished without coming down. Also, a cable of carbon nanomaterials can be made incredibly strong without much weight.

So now we have a balloon that can stay high in the atmosphere, above most of the clouds (but not all, because then it wouldn’t be able to make its own hydrogen) and tied to the ground with an essentially unbreakable cable. What is that good for? This brings us to a neat feature of carbon – it is an electrical conductor. In naturally occuring forms like graphite, carbon has a lot of resistance, so it is used for lighting elements, but early research with nanotubes and nanowires suggests that they can be quite efficient conductors. So what we’ve got is a wire leading into the sky as a permanent installation, 12,000-20,000 metres long. As the wind acts on this it pushes against it a bit, but if the balloon is lifting strongly enough it will resist the effects of the wind, and a huge amount of friction gets generated across the whole length of the tether. This is do two things – one, it will create a very strong static charge – more free electricity. Unfortunately, the other thing is draw lightning. This is free electricity happening rather faster than easily managed. However, we have spent a lot of time getting good at redirecting lightning that hits our power lines, so we have a temporary solution. Ultimately though, we may be able to build capactity to capture lightning strikes and use them more productively.

So free power is one use, but there are many others. Tethers could be used as launchers for gliders, blimps, and drones of all types. A set of electromagnets could be wrapped around the tether, and use the same principles as a monorail to lift almost any payload (assuming a large enough balloon). It could be used in the same way to bring blimps and dirigibles down, against their lift, so they wouldn’t have to power themselves down with their maneuvering engines, which would make them lighter and leave more lifting power for cargo.

A tethered balloon is a major hazard to navigation of air traffic, but it might be possible to put sensors along the length of the cable, and use stored electricity to “flex” the cable out of the way of flying hazards.

In part four of this series, I will discuss dirigibles – blimps with an internal frame structure – one of the most interesting applications of these carbon nanomaterials.

Flights of Fancy – Part 2

In Part 1 of this series I lay out the idea of a really large solar power installation which, instead of generating electricity for export, uses the power and heat for creating carbon nanowires, nanotubes and carbon-neutral synthetic fuels.

In Part 2, I am going to discuss a few products that are possible with these materials.

Carbon is very strong for it’s weight, and can be woven into lots of different materials – mostly very strong fabrics, and solids when combined with glue.  That is with irregular, randomly assembled carbon fibre.  Carbon nanotubes are extremely fine tubes of carbon perfectly arranged in long, regular chains.  These are vastly stronger than carbon fibre, because of their shape and the molecular bonds – these bonds require a great deal of energy to create – that’s why they are energy-intensive to make.  They also require tremedous energy to break.  Carbon nanowires are strings of carbon one atom wide – orders of magnatude smaller than any other material, and hugely strong.  With filaments like carbon nanotubes and nanowires, you can create massively strong cables and fabrics that are also lighter than anything else we create.

So what do we do with light, strong fabrics and cables?  Well, anything that we currently make with carbon fibre is an obvious candidate, like bicycle frames, auto parts and fighter jets.  These bind carbon fibre in glues and resins, because the carbon fibre is prone to destruction with any kind of abrasion, and because, compared to nano-materials, they are disorganized, they have limited lifespans, stretching out and breaking down over time.  What I think are the killer applications for these materials are blimps, balloons, dirigibles and tethers.

I am going to take these applications one at a time over the course of this series, and then posit some specifics that I think are interesting ways that it would change the lives of everyone, everywhere.  As an aside, changing the lives of everyone, everywhere is what science fiction is based on, but in business is called disruption, which puts some entities out of business and creates opportunities for others.


A blimp is a non-rigid airship.  They are inflated by a gas of some kind which is lighter than air, so they rise, and they don’t have anything inside the envelope to provide extra structure.  A relatively small pod, called a gondola, with engines and steering mechanisms is attached to the bottom of a blimp.

Carbon nanomaterials can be used to build blimps that are much lighter than previously possible.  The maximum size of a blimp is set by how much pressure they can contain, so blimps can get bigger using carbon materials, and they bigger they are, the more they can lift.  Using super-strong nanomaterials for gondolas will help them increase their size too.

The big issue with blimps and other lighter-than-air aircraft is the choice of gas used to fill them.  There are really only two choices – hydrogen and helium.  Helium is much, much heavier than hydrogen, it is expensive and hard to find and replace.  However, helium doesn’t explode, so it is much preferred at the moment.  Hydrogen can be created with electricity and water, so any industrial-scale solar installation with a water source can generate any amount of hydrogen for free.  The “no-explody” part of blimps is largely an engineering problem – there will be some risk, but it can be minimized.

So what do you do with larger, lighter blimps?  Today they are used to things like surveillance – they can cover their upper surfaces with solar panels, use lightweight, high powered electric fans and they can stay up for a long, long time.  Remotely or robotically piloted blimps could be made to stay up all the time.  They are being sold right now to hover at 80,000 feet and watch over battlefields or borders, but they could do much, much more.  With a robotic pilot they can present much lower risk than human pilots, and they can more effectively do battle with they great enemy of airships – the wind.

A blimp, even a really large one, is not well-suited to bulk cargo because of the limits to their size, but they could do anything a helicopter can do, and do it more safely.  When a blimp loses power, it doesn’t fall out of the sky.  That means that you could use blimps as cranes in remote areas, in urban areas, for search and rescue, and for sightseeing.  They are limited in speed because of air resistance, but they could be made more streamlined with the stronger materials, and if we are able to make more powerful electric motors they could conceivably be able to navigate in extreme conditions.

Because they can use solar power to produce lifting gas and propulsion, it could be possible to ship a blimp deflated, set up its solar panels next to a water source, and within a relatively short period of time it could self-inflate and be ready to deploy.  Getting high-value, low-volume cargo like medicine to a remote area could be made much easier with a cargo vessel that can travel day and night without needing to refuel.  The surveillance-style drone blimps could also act as replacement communications infrastructure in the event of natural disasters, acting like a satellite relay for much lower-power transmitters, even arranging in self-organizing and self-healing swarms to provide cell phone coverage after all of the cell towers have been destroyed or disabled.
Imagine a remote village in Nunavut has a bear break into the pharmacy and destroy all of the medicine for a community.  A teaching hospital in Saskatoon could assemble the necessary medicines in a blimp-ready cargo pod, take it to the roof in time to be picked up by a robotic blimp sent from Regina only hours after the call for medicine, and it could be in town within a couple of days, even in difficult or impossible conditions for a heavier-than-air aircraft.

Part three of this series will be discussing balloons and tethers.

Flights of Fancy – Part 1

I have been thinking a lot about the possible technological, ecological and social consequences of a really robust investment in solar energy production.  Much of what will follow is not based on specifics – I am not an engineer, and I don’t have easy access to the numbers, but I will refer to many existing technologies and the extrapolations are not outrageously unlikely.

To begin, let’s assume that you can generate a lot of electricity via a solar power installation.  There are a few ways to do this – photovolaics are very commonly seen these days, but you can get better efficiency out of mirror-based, thermal plants.  These plants are really neat, in that they use salt to absorb the focussed heat of the sun, and use that molten salt to drive steam turbines all night, so that a solar plant can generate electricity around the clock.  There is a lot of maintenance in any power plant, but this maintenance is the only ongoing expense in a solar plant – no fuel needed and no waste to dispose of.  This part isn’t fiction – these plants exist, and they are generating power right now.

Here’s where my thoughts diverge from what people are doing with solar power right now.  Right now, people are mostly generating power with solar plants – power which competes in the same market with nuclear, wind, hydro and combustion power plants.  This creates the opportunity for the incumbent players in the power generation market to manipulate that market, by supplying power more cheaply to discourage an outsized investment in surplus solar power generation.  Here’s where I think investment in solar power can diverge from the problem of contributing to a power grid that must be balanced across the loads of half a continent.  If your goal is to generate as much power as possible, perhaps with many plants clustered together, what is possible with unlimited free electricity – not truly free of course, but not defined in price based on the rest of the grid.

The answer, to my mind, is carbon.  Specifically, carbon nanotubes and nanowires.  These are materials with amazing properties, but they are scarce because they are difficult to make.  They are microscopically fine filaments that are incredibly strong and, when combined, incredibly tough.  They are an ideal product to produce with a surplus of solar energy – because their scarcity can demand a higher price per watt than exporting the electricity.  There is another cool side effect – the carbon feedstock for this process can come from the air.  Sandia National Labs has demonstrated a process that captures atmospheric carbon on a cobalt-iron ceramic element.  There is a significant challenge to industrialize the process to convert atmospheric carbon to high-quality carbon nanotubes and nanowires, but for the rest of this series, I’m am going to take it as a given.

As an aside, the process demonstrated at Sandia National Labs used the carbon captured to create synthetic fuels that are carbon-neutral, because the carbon they release when burned has already been removed from the atmosphere.  This is another secondary benefit of a solar-based energy surplus.

Part 2 of this series extrapolates from the above and discusses what might be done with carbon products if they were available in industrial quantities.