Archive for July, 2015

A few developments that I think are interesting and worth following

July 2, 2015

No particular updates on my game project at the moment unfortunately.  I have been thinking a little about a couple of other things of a slightly more abstract nature – namely model selection and generalisation of the concept of the idea of the radical of a number – but these, too, are works in progress.  Of course, Unity 5.1 is now out with the first phase of Unity’s new multiplayer networking API, but I think I’d like to take the Bolt and Zeus client-server architecture for a spin first, and see where that leads (though interestingly enough, it now appears that Bolt has been acquired by Photon, one of the bigger players in multiplayer networking who have, amongst other things, targeted Unity3D games as part of their strategy).

So instead of talking about what I’m up to currently (in terms of my hobby projects) I thought I might instead share a few findings with you, the reader, that I think are useful and important.

1. Desalination using nanoporous single-layer graphene

One of these things is a recent article (as of March 2015) published in nature nanotechnology, here, on desalination (news digest here).  There are a number of things here that are significant:

  • The use of nothing except for graphene membranes, ie, carbon, so potentially a fairly cheap thing to produce
  • The potential for an almost 100% salt rejection rate
  • The high potential throughput (up to 10^6 g m^-2 s^-1), albeit induced via an applied pressure differential

So quite exciting.  It looks like, with an appropriate implementation, that this sort of technology could lead to relatively cheap clean and fresh water (certainly cheaper than current techniques, which are based on either brute force methods (such as heating the water and collecting the vapour), or electrodialysis reversal (which has been in commercial systems since the 1960s)).  And water is fairly important to have to hand.

2. Single stage to orbit spaceplane ‘Skylon’ on track, target date 2019-2022

Reaction Engines Limited seem to be making good progress on their SSTO spaceplane concept.  This relies heavily on the Sabre engine, which through 3D printed nanotube components, has the following capabilities:

  • Can cool air from 1000 degrees celsius to -150 degrees celsius in 0.01 seconds.
  • Using proprietary methods and techniques, the critical components of the engine are impervious to frosting over at subzero temperatures.

In the last few years, the company has had the following nods of approval from various governmental bodies and organisations:

  • A 60 million pound funding injection from the British government in 2013
  • Feasibility study conducted by the ESA, leading to their seal of approval in 2014
  • Feasibility re-affirmed by the United States Air Force Research Laboratory in 2015

Furthermore, it now appears that the project is ramping up, with assistance and expertise being provided to REL from the United States, and the hiring of various people to the program with decades of experience working in the industry.  So very promising.  The target date for potential test flights of the full blown SSTO craft could be as early as 2019, with supply runs to the International Space Station by 2022.

The great thing about this project mainly is cost / kg in delivering a payload to orbit.  Building a spacecraft using these techniques could lead to stupendous gains in efficiency, decreasing costs from the current £15000/kg down to £650/kg.  In other words, this development could lead to the solar system being opened up to for potential commercial use (albeit, hopefully regulated by an appropriate global agency), and would certainly make it possible to construct interplanetary spacecraft (for manned missions say to Mars), or logistical waypoints for the support of asteroid mining operations in orbit from shuttle runs, for instance, at significantly reduced cost.  Naturally, this in turn (initial support of targeted asteroid mining operations say within the window 2030-2040) would address another problem, which is the increasing scarcity of rare earth metals (although recycling could be a partial solution there).

3. Agriculture in arid areas

Something that I continue to follow are the developments in the still as yet nascent area of farming in arid areas, using little more than seawater and sunlight, to produce food for consumption.  The reason for this interest is that there is no shortage of seawater and arid areas relatively close to the sea in the world, so there is a considerable opportunity for innovation and growth in this area.

There are a few projects in particular that I am interested in here:

Both Seawater greenhouse and Sundrop farms use a similar form of system to operate – they pump saltwater either from the water table (if close to the sea), or from the sea, into greenhouses.  Evaporation driven by solar energy then causes the water to cool the greenhouse and irrigate the plants inside.  This is a gross oversimplification, of course, and there has been decades of work done to polish this general outline, but that is the idea.  There are certain other risks of course that one needs to deal with with such an operation as well, such as maintenance costs, not to mention how one might deal with a 5 metre sea level rise, or occasional storms.  Regardless, it appears that now the technology has become mature enough in this instance to start paying dividends – in a recent press release Sundrop farms announced their partnership with Coles supermarkets.

The ISEAS project is slightly different.  It uses saltwater ponds to grow shrimp and fish for food, mangroves to purify the saltwater, and plants grown with the purified water to provide nutrients for the ponds (closing the loop) and also provide oil (in their seeds) for biofuel production.

So it looks like there is a fair bit of promise in this general direction.