Can we go 100% renewable – I don’t think so but with a good mix we can get close…
in the UK energy use is around 5kW per person per day of which 1kW is electricity – the rest is gas, cars, machines – domestically and industrial. We need to get down in total to around 2 kW per person per day. In the USA it is more at around 10kW pp and worldwide it is around 3kW. Can the planet sustain an average of 3kW pp for the whole world (and what of the future as world population grows?). Can we generate 20TW of power spread over nuclear, solar, geothermal, wind and biomass?
Wind, , tidal, bioenergy, solar, batteries are all good new, green and renewable (almost) ways to solve our energy needs but we need to look further. Wind is intermittent, tidal and wave expensive and difficult – look at the two Scottish companies Aquamarine and Pelamis for some lessons (though there is Maygen) and whilst the Swansea Bay tidal scheme looks promising it too is expensive and way off in the future. Battery power – very good but what does one charge the battery with – power from a coal powered generator. And does de-carbonising cars mean we need three times the energy we use now?
There are the old arguments put forward, e.g. for 100% solar fuel to power the world the farm would cover the of the UK; for a wind farm it would be the tenth the size of Europe. Well all that is slightly old hat as cells and windmills are getting more efficient. Both energy sources are transient of course and with solar there is the problem of the Grid connection though last July 2015 99% of the home energy came from solar. Recent Li Ion batteries now exhibit only 10% loss in charge and delivery so there is hope though Tesla batteries go much further but are much more expensive. Yes to solar farms too but it does not generate enough and is intermittent too though new very dark materials exploiting nanotechnology (reflectivity of less than 1%) will help in the efficiency. Solar power plants have a field of mirrors concentrating sunlight onto a central tower containing tubes that heat up gas to drive the turbines.
No, in the mean time until these technologies become affordable and scalable, we need to get fracking (or to continue to push fracking since we’ve effectively been doing it to get oil out of the ground for 20 + years) and give Mr Putin something to think about. Yes convert coal stations to gas; yes to biomass (trees – but steady on we need to grow back and keep the equilibrium, plankton – long time in the future). Our carbon footprint needs to come down from the 10 Tonne per capita/per year. Our gas use is 100 Gm3 per year; total Shale output could be 10Tm3…Global oil use is 100M barrels/day of which 1 million barrels per day comes from the North Sea.
Other energy techniques to continue :
From solid latent heat of melting/freezing – see Sunamp.
Water flow – small scale but expandable e.g. The Water Engine.
Tidal – Swansea Bay £1B for 300MW (Swansea’s population) and requires subsidies of £156 per MWh (more than the cost of wind/solar).
Equitix – Atlantis/Meygen tidal project – Pentland Firth. Soon to be in operation. Atlantis is AIM listed. 500MW – revenues 235K shares at 73p. pre-tax loss of 4M. Covers 3H = 7 football fields.
Also the proposed West coast barge in the UK – stretching from the Bristol channel up to the Solway and providing bridges over them (Forth barge bridge anybody?). This will provide around 4GW of power daily and cost £12B.
Kinetic Energy from buildings – Vibration, movement and sound can be captured and transformed into electrical power using piezoelectric materials.
Lighting systems – blue LEDs (problems with light pollution and animal physiology and behaviour ettects, but good on cost, control of intensity but physiology & psychological problems on animals and light pollution for astronomers – amateur and professional). Laser LEDs are also in development and will produce more luminance than ordinary diode LEDs.
Smart buildings, cities and grids will help increase our fuel efficiency and lower our footprints…ground source heat pumps (heat from the ground), thermal mass (energy stored in materials and to be used later), water source heat pumps.
Other off-Grid solutions…
Battery power and storage, fuel cells – solar photovoltaic, Li-ion, hydrogen, Redox-flow…
An interesting story concerning fuel cell vehicles: some fuel cells work by converting Hydrogen to water and releasing energy in the process. A FCEV ( fuel cell electric vehicle) powered by a fuel cell “charged” from the European Grid (hence half of power is from oil, gas, coal) was found to be outperformed (equivalent litres fuel per 100 km) by a compact gasoline and battery electric car. (Energy & Environmental Science 10.1030/C5EE01082A).
I passed an electric car charging in Glasgow the other day. It seemed to be charging at 0.08 KWH per minute and up to a “charge” of 7.5 kWh. A car needs around 50kW power (my bike when pushed hard (metaphorically speaking) needs 1kW) when running on the flat for 50 km/h ; I hope it was a hybrid…though I’ve heard pure EV cars can do 100km on a full “tank” of 25kWh though if powered by Tesla they can go up to 250 – 300 km.
Could hydrogen be produced by coal-gasification – just a thought?
Tesla batteries (Li-ion)of course – for storage and to go hand in hand with home solar panels/windmills.
Don’t forget Peat – Peat store half of UK carbon ~ 5 BT (40x that of forest) and other alternative fuels – take a look at Scottish start-up Celtic Renewables who produce biobutanol as a by-product from the Whisky business.
Energy from seawater? – subject sea water to electric current to release gas; isolate CO2 and H2 and heat; CH4 is a by product and the CO2 and CH4 form long chain unsaturated hydrocarbons that can be converted into fuel with a Nickel catalyst.
Consider also – Phytoplankton – biological C capture – should concentrate on this rather than emphasis on green tariff. Also convert to carbonate – solids
Batteries from atomic waste C14 put into diamonds… Generates 15J a day-1KWh over 1000 years. Compare to 60kWh Tesla battery 10-50KWh over 5 hours.
So – nuclear power please! keep up with the old stuff (but perhaps a 4GW Hinkley plant is putting all ones eggs into 1 basket – perhaps go for more smaller scale plants and further explore using lower grade uranium as fuel) but keep on at my first area of research – nuclear fusion. Of course a final solution will be a mixed one – nuclear with wind, bio, HEP, battery, solar, tide etc..
A Fusion reactor using 45 litres of water (bath tub) producing 1.5 g Deuterium and needing a mobile phone worth of Lithium (for equal amount of Tritium) produces 1TJ of energy (100 Tonnes of Coal) – a 1GW coal station needs 10,000 Tonnes coal per day – and think about the CO2 footprint! Drax power station used to produce around 20MT of CO2 per year (4GW plant though it is being continually updated to biomass which has roughly the same energy content as coal – sometimes more).
We have the proposed ITER of course and the LLNL in the USA for two different types of fusion reactor. Now on the scene are small companies, startups in their own right, with strong ideas for tokomak size and design. Such small companies can exploit highly practical rapid iteration development techniques only available from private investment (eg. Bezos Expeditions, Mithril Capital Management, Vulcan, Goldman Sachs) and cutting the top-heavy management stuctures and government funding of ITER and LLNL.
There are two way of creating fusion from a plasma- either using a Tokamak for magnetic confinement (ITER) of the plasma or intertial confinement using high powered lasers (LLNL).
Here is a summary:
Tri-Alpha Energy – California – smaller Tokomak using particle physics collider techniques and the plasma itself providing the magnetic field. Dimensions – 23 metes long, 10 metres wide.
General Fusion – Vancouver. Magnetised target fusion – liquid metal inject plasma and squeeze technique. Protons/Boron. – no neutrons for fuel.
Helion Energy – Washington – colliding plasmas in rapid pulses.
Industrial Heat – Raleigh N.C and its low temperature Ecat machine (Ponds & Fleischmann ring any bells?)
Some of these start-ups are backed by some of North America’s finest philanthropists – Jeff Bezos (Amazon), Paul Allen (Microsoft), Peter Thiel (PayPal).
Lawrenceville Plasma Physics N.J – hydrogen-boron fusion and the dense plasma focus device.
Tokamak Energy – Oxford – spherical tokomaks and high superconductivity techniques. Feb 2017 gets £10M of UK govt.
LLNL – California – state sponsored researches the National Ignition Facility (NIF) that uses inertial confinement – having a hard time December 2016.
ITER – south of France worldwide collaboration – magnetic confinment, cost at $20 billion and counting – 5 times the LHC. Large Tokomak 30 metres tall and containing 850 metres cubed of plasma. Management, cost and Brexit problems as has JET with the latter.
exhaust pipe of the reactor vessel – which removes the spent Helium (Ash) from the reaction. – the Divertor and what it is made up from (Tungsten?). Feb 2-17 – West Tokamak at Cadarads (ITER) doing good work on divertor – a trial ground for the ITER.
ASDEX prepares the way for ITER.
Lockheed Martin – Skunk works – compact fusion once again using a cylinder form of the plasma containing vessel – and in 2020 producing 100MW.
MIT – public funded research – smaller scale and using superconducting technology – 2016 out for finance reasons.
General Atomic – but only one going 2016.
First Light Fusion Ltd – UK who use the internal confinement fusion technique and advanced implosion processes.
CCFE – Culham Oxford – home to JET (Deuterium/Tritium mix fuel), one of the pioneers of fusion many years’ ago and MAST. The Mega Amp Spherical Tokamak (MAST) uses a spherical, cored-apple shaped plasma rather than the doughnut one and methods of venting unwanted heat are also being explored.
In Asia the KSTAR projectis a tokamak-typed nuclear fusion reactor being run in South Korea – coming up with some good plasma lifetimes. H-confinement times 1.0+.
In Germany Wendelstrien Stellerators where plasma is contained in the magnetic field – a pentagram shape. Complex. Part of Max-Plank institute, at Griefswald in NE Germany – 7 times out what put in, recently for a short time I suppose…?
Then this EMC2 Fusion
Applied Fusion Systems – Chelsea London – recently founded by entrepreneur Richard Dinan?
Fuel for these fusion processes comes from Deuterium and Tritium – both Isotopes of Hydrogen. Deuterium form water, Tritium from Lithium (and neutron reaction within the fusion process) – or from the Moon (helium-3)! The free neutron reaction produces radioactivity and therefore waste. General Fusion’s liquid technology gets around this by catching the neutrons with lead and using helium-3 which produces fewer neutrons. Tri-Alpha plan on using fused protons with boron-11 producing no neutrons but needing higher temperatures.
Fusion will provide a constant source of energy unlike solar or wind but needs a high gain (Q – energy out/energy in) and this needs to be around 15 to 20 and the energy has to be somehow put into the existing grid infrastructure. Lower cost, smaller reactors can produce values of Q similar to that required by ITER and do this by focusing on the beta factor of the plasma – the ratio of plasma pressure to magnetic pressure (Q is approximately related to the square of beta). US government agency ARPA-E launched a program in 2015 to support alternative approached to fusion. – midway between containing plasmas and systems for heating and compression.
In the meantime there is Fission to continue…
Magnox – closing 1GW gas cooled reactor using natural rather than enriched fuel. Originally came from need for plutonium from the defence industry. Used Magnesium Oxide as the reactor cladding hence Magnox.
AGR – (next step after Magnox) – enriched fuel. CO2. Natural fuel.
LWR (Light water reactor) – water cooled.
LWR are pressurized water (PWR) or advanced boiling water reactor. LWR uses low enriched fuel and water as coolant and moderator.
Or go to the EPR (European Pressurised Reactor – 1.6GW) of the kind proposed at Hinkley Point. (Horizon, EDF, China big money). But only 4 built worldwide and have had problems. UK Govt set electricity at £93/MW – any more the punters will pay.
Hinkley A Magnox
Hinkley B PWR
Hinkley C – EPR?
Then Generation IV design – Sodium cooled. Molten-salt – no melt down – but still ontable.
Smaller stations mean production type process rather than one off cathedral style (Gaudi like! – but beautiful!).
UK has 14 AGR, 1 PWR.
Dec 2016 – French reactors having a hard time – some shutown for problems…