Current Popularly Proposed Solutions
Looking at various solutions and partial solutions which are often suggested & problems with them
Just use renewables
Problem 1: variability of production is a big problem – we need confidence that energy is available when we need it, and hence, to cope with the production variability, we need a background source of energy or a huge amount of storage to fill in the “gaps”. The “gaps” are currently filled by gas turbines – burning methane to produce electricity, which produces CO2. That seriously needs to change.
Problem 2: on a country-by-country basis, there is not enough energy from renewables to provide all our energy needs. Very long distance transport of electricity (e.g. from equatorial deserts to where most of the population of the world lives and works) would lose a lot of energy on the way and requires significant global political cooperation. It might be viable in the long term, but it is not a possibility in the time scale in which it is needed to solve the problem with global warming. The energy we use running people’s homes is a small proportion of the total amount of energy we consume just by living. Look at Sustainable Energy Without the Hot Air for an analysis.
Thermo-solar plants help by storing the heat from the sun, so that they can continue to produce electricity from the stored heat overnight or on cloudy days, but they are huge, so OK if sited in hot places where there is a low population density, e.g. in deserts nearer the equator, but not so good in densely populated areas in the northern hemisphere.
Hydrogen
Move to a Hydrogen economy
Problem 1: The standard industrial preparation of hydrogen is called steam reformation of methane – which effectively burns “natural gas”, a fossil fuel, and produces CO2.
Problem 2: Hydrogen is light volatile gas, which is harder to store than liquids like water or petrol. Hydrogen is also far more difficult to contain than methane or DME as its molecules are much smaller. So tanks to hold H2 need high pressures and very cold temperatures.
Problem 3: Hydrogen is colourless and odourless, so leaks are not easily detectable, and leaking hydrogen can explode, just as easily as methane. Does anyone still remember the Hindenburg disaster?
Problem 4: If hydrogen is produced from steam reformation of methane, then it would be more efficient just to use the methane directly – there is more energy from burning a molecule of methane, than from burning the 4 atoms (2 molecules) of hydrogen you would get from that methane molecule, and the steam reformation process produces the CO2 in any case!
Note: Methane is so much worse for global warming than CO2, that either burning methane, or using it to produce hydrogen or DME or some other liquid fuel is actually better, in terms of global warming, than letting the methane escape into the atmosphere.
No Nitrogenous Fertilisers
“Make farming organic” is often proposed in the media implying that then no nitrogenous fertilisers would be needed, which would reduce the energy cost of agriculture.
The third agricultural revolution – also paradoxically called the “Green revolution” https://en.wikipedia.org/wiki/Green_Revolution has taken much of humanity out of starvation. It has also allowed the world population to grow very rapidly.
Problem 1: We would need six times more land area in farming production to produce the same food if we did not use nitrogenous fertilisers (soil association discussion on ‘Farming Today’ early on 23 Oct 2019). Moving to mixed farming, with animals in rotation on the fields, so that animal manure is used in place of some fertiliser is probably good, but animals produce CO2 and methane too.
Problem 2: There is insufficient land area globally to produce enough food organically to support the world’s population. The problem is exacerbated by the requirement of land for PV and wind farms, not to mention growing of bio-fuels.
Problem 3: Most “carbon offset” schemes come down to paying people to plant trees, which again needs fertile land. So a purely organic approach will not work.
Problem 4: Another, currently encouraged, method of carbon capture is BECCS – growing “energy crops” to produce bio-fuels, or to burn for energy, whilst also capturing the CO2 produced when burning. This also needs fertile land.
Proteins – the essential building blocks of plants and animals need nitrogen. Though the atmosphere is 80% nitrogen, most plants cannot absorb or use it. A small number of plants are capable of “fixing” the nitrogen – typically peas and beans – which is why these were used in crop rotation in pre-industrial days. If we were to adapt the “fixing” technology to make all the plants we grow fix their own atmospheric nitrogen, then maybe we would need less of the fertilisers.
Problem 5: In theory, we could develop nitrogen-fixing varieties of crops, such as wheat, rice and potatoes. This would however, involve Genetic Modification of these crops, which has met with widespread suspicion and resistance throughout society, often as a result of sensationalist media reports.
Electric cars
Replace all fossil fuel powered vehicles with Electric ones
For this to be a global solution, we need to provide sufficient batteries and electrical infrastructure for all the cars and all the trucks in all countries.
For transport purposes, we need batteries to store a lot of energy and be both small and light. To fulfil these constraints, batteries for transport will have to be based on Lithium.
Problem 1: It is unclear whether the world possesses sufficient easily extractable lithium, though lithium battery manufacturers claim it is not a problem.
Problem 2: Furthermore other “rare earth metals” are needed to make a viable battery. Cobalt is currently a problem, as it comes from politically unstable countries, mostly the Democratic Republic of the Congo (DRC) and Zaire.
Problem 3: Many developing countries do not have a sufficiently reliable electricity supply even for domestic use. Trying to expand their electricity supply to cover transport as well, is not viable in the short term. This again is possibly a solution for western, developed nations, but not a global solution. Providing a CO2 neutral liquid fuel would be a much better, truly global, solution.
Carbon Offset / Carbon Pricing
Carbon Offset schemes and Carbon Pricing
Superficially, charging people for emitting CO2 makes sense, as it will discourage them. This is often called ‘carbon offsetting’, where companies are allowed to off-set their emissions by paying someone else to plant trees, usually a third world country in a far-flung place, not directly visible or accountable.
Problem 1: Sadly, this is never going to work on a global scale. Apart from being wide open to abuse and corruption, it is basically pushing our problems onto those who cannot afford to stand up to us, and simply not taking responsibility for cleaning up our own systems.
We actually need to solve the problem, using our inventiveness, and then make that technology available to everyone so that the whole world, including ourselves, can benefit and indeed survive.
Problem 2: Carbon pricing encourages “carbon expensive“ processes to be relocated to a country that either charges less or doesn’t implement carbon pricing at all. Such a relocation has no effect on the CO2 produced, and may make things worse, as the manufactured products now require to be shipped round the planet.