Keep your hands off the Moon
I think I was supposed to be excited at the prospect that the Moon might be mined commercially, but I am not.
What have we done to our own planet? We have plundered its resources, poisoned its atmosphere, polluted its rivers and filled its seas with garbage. We have managed to pollute even the space around our planet with our junk.
Instead of starting to wreck another environment with our apparently insatiable appetite for throwaway goods or luxuries that we enslave ourselves to debt to buy, we would be better cleaning up the mess we have already made and distributing our assets more evenly across our own planet.
J A G Brown, Gloucester
Replaceable batteries could keep electric cars on the road
A lot has been written about the range and refuelling time for electric vehicles. However, in the clamour for rapid charging and the provision of charging stations, the use of easily replaceable battery modules is rarely mentioned.
Is it so impossible to configure a larger version of the system used for electric drills? Swappable battery modules might not fit into small cars but small SUV-sized vehicles, and larger, might be designed to take them.
The system would be similar to that used for propane and butane cylinders. At the refuelling station, there would be cobots to help take the used battery out of the vehicle and replace it with a fully charged one. The price of any remaining charge in the used battery would be deducted from the cost of the exchange unit. Refuelling would be quicker, cleaner and safer than having to stand on a windy forecourt pumping petrol.
The battery units would have to make good thermal contact with the vehicle for cooling. Rapid charging would not be necessary, however, so the associated thermal problems would not occur. Slow charging at home would still be possible.
Standardising the modules would enable refuelling at any roadside station. Also, the rescue services could carry spare modules to vehicles stranded after running out of charge.
Clive Renton, Chippenham, Wiltshire
Let's back the Moltex system
I fully endorse Rich McEachran’s analysis of the dire situation for our energy supply, and that there is an essential need for strong investment in nuclear to secure our future.
However for nuclear to significantly advance it needs to achieve high safety, much reduced cost, be able to load-follow, address legacy waste and achieve non-nuclear proliferation.
Sadly I cannot concur with Rich’s proposed solution as Rolls-Royce even in their marketing brochure which shows their system with elaborate safety systems openly admits their generational costs will be similar to current nuclear systems. These are widely acknowledged as much too high.
By contrast the British-developed Moltex small modular reactor solution would appear to be the only system to fully achieve all of the above requirements. Its unpressurised high output temperature system with negative reactivity (it naturally shuts down at 900°C, well below deformation levels of the steels used) makes for a compact unit, much cost reduced, and so reduced nuclear island. With its high temperature output, and load-following capability, it not only gives better thermal efficiency but it uses competitively priced generating equipment.
The Moltex system has been rigorously peer reviewed, demonstrating power prices highly competitive with the best on offer today, unlike the Hinkley C costing. Their emphasis on recycling spent fuel, and in time the use of thorium as fuel, address the other two criteria.
It is a great tragedy that this excellent British invention, which could provide many jobs and much-needed export potential, should fail to get backing in the UK and reluctantly have to go to North America for support, which is amply on offer, in its final drive to meet the costs of regulatory approval.
K Bunker, Basingstoke, Hampshire
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