Boris Johnson The Liar is no longer Prime Minister?

Amid a dramatic series of resignations of government ministers over the last 48 hours, Boris Johnson has finally resigned his post as leader of the Tory party. Normally this would mean that he is also no longer Prime Minister but nothing is normal concerning Johnson! Like others before him, he intends to stay in the role until a new party leader is chosen but the chorus of voices saying that they don't trust him to fulfill the role of caretaker is loud and growing. His record is against him!

Of course we all know that Boris Johnson, in his time as the Telegraph’s Europe correspondent, made his reputation by inventing Euromyths about straight bananas and one size fits all condoms etc.; in effect creating the Big Euromyth which he used together with the big red bus "£350 million a week" lie, to narrowly win the Brexit referendum. 

As Prime Minister he has lied repeatedly and presided over probably the most corrupt and unprincipled government in UK history, but when I saw this interview with Chris Patten, in May 2016, I was surprised that he was able to call Boris Johnson a liar so directly and without any risk of legal proceedings for slander (from 1:42).

I investigated further and discovered that Johnson was sacked from the Times in 1987 following a story in which he fabricated a quote from his godfather, an Oxford academic, who was ridiculed for Boris' inaccuracies.
  

He has also been sacked from Michael Howard’s shadow ministerial team in 2004 for lying to Guy Black, (Howard’s press secretary), David MacLean (the Tory Chief Whip) and the Press about an affair that he was having with Petronella Wyatt that resulted in her having an abortion. 

But the most revealing episode of his character so far has been in a recorded telephone conversation with Darius Guppy, one of his Old Etonian chums, in which he agreed to get the address of a News of the World journalist, Stuart Collier, so that Guppy could arrange an assault intended to scare him off investigating a fraud case in which Guppy was involved. This took place in 1990 when Johnson was the Daily Telegraph's Europe correspondent. In an interview with Eddie Mair, Johnson subsequently denied that he had done anything wrong and said that he was just humouring his friend.  

Judge for yourself whether he was asking Guppy questions about how much he was going to hurt Stuart Collier in order to humour him. 

Someone has requested that this video be age restricted by Youtube even though it contains no content likely to disturb anyone, even a young child. I suspect political interference!

https://www.youtube.com/watch?v=iDJWkS2A9T0 

We are now in a period of post-truth politics in which skilled individuals, who are good at saying what people want to hear, whether it's true or not, can rise above reasonable and sensible discussion and get away with it.

Did the 92,153 Tory Party members who elected him really want a proven liar leading the country? 

I know I didn't!

Why has Putin isolated himself?

 

After the meeting with Macron it was said that the separation was necessary because Macron refused to be vaccinated by a Russian vaccine. Well,who would allow the Russians to inject them with who knows what?

But does that explain why he has separated himself from his security council like this?

Or why he is seated so far from his Minister of Defence and Head of The Armed Forces.

Is he scared of covid, or is he perhaps afraid of an assassination attempt?

In either case it offers a graphic insight into his state of mind!

Germany’s Folly

Germany is learning a hard lesson about relying on Russia as a trading partner at the same time as closing nuclear power stations and putting all your faith in wind and solar power.

In 2011, after the tsunami and the resulting release of radioactive material from the Fukushima nuclear plant, Angela Merkel and the German legislature decided to pursue an energy policy under which nuclear power would be wholly replaced with renewables, the “EnergieWende”. In 2019 they also decided to close all coal fired power stations by 2038.

Coal and nuclear plants are base load generators which reliably produce electricity 24/7 at a steady output. Apart from hydro, renewables such as solar and wind are by contrast, weather dependent, variable and can be unproductive for days. Like other countries aggressively pursuing renewables, Germany currently has no technologies which can provide energy storage on a grid scale that will be sufficient to cover for periods of low output from renewables.

So if you have abandoned coal and nuclear, and wind and solar are not productive, what other options are available.

You could import oil or Liquefied Natural Gas LNG. In 2018 Germany’s oil imports represented 34.3% of their primary energy consumption, but practically none was used for electricity generation so the infrastructure is lacking. LNG in Europe typically comes from Russia or the Middle East and has to be transported by specialized ship from its place of production to ports in Europe or on other continents, which makes it expensive. Furthermore, recent wars make one question the reliability of LNG supplies in the context of energy security.

Germany's primary energy source of choice, to fill in periods of low renewable output, is natural gas. Germany has no gas of its own and buys it from many countries but the largest share is from Russia. In December 2021 the Federal Office of Economics and Export Control showed that 34% of its total gas supply came by Russian pipeline. This is, or was, expected to increase as more renewables are brought online. So Germany was going to become more and more dependent on Russian gas.

Germany also imports coal from Russia. The coal group VDKi said 53% of hard coal received by German power generators and steelmakers came from Russia last year.

Therefore, as recent events have brought sharply into focus, Germany’s energy security is highly uncertain as a result of both the EnergieWende and over-reliance on Russia.

In January 2022 Germany closed three operational nuclear power stations thus removing 4GW of base load generation capacity. It plans to close the remaining three plants next year. This is at a time when energy prices are soaring, and at 0.24-0.30 Euros /kWh, Germany already has the highest in Europe.

Contrast this with France, which in the seventies after the oil crisis, decided to build a fleet of nuclear power stations in order to reinforce and maintain its energy security. It currently exports 3bn Euros/year of electricity to its neighbours and its energy costs are  0.13-0.15 euros/kWh.  France has just announced that it will build six more nuclear plants.

Following the violent behaviour of Russia, and its oppressive rulers, Germany is now facing the harsh reality that the largest share of their pipeline gas supplies may be cut off.

This was all totally predictable and I am astonished that Germany’s rulers could not foresee the potential dangers of their short-sighted decisions.

It seems that some Western politicians can be as deluded in their assessment of risks, and their world view, as any Russian dictator.

Energy and the Climate Crisis

The Climate Crisis

I’m sure that most, if not all of us, agree that climate change, due to man-made carbon dioxide from burning fossil fuels, is the single most serious challenge facing the world today. 

July 2021 Eastern Belgium

So what is the best way of tackling the problem of a global rising energy demand and demand for electricity in particular, at the same time as limiting or even reducing to zero, the emission of man-made greenhouse gases? 

This is a complicated and wide ranging subject and addressing it has resulted in over 10,000 words so, in order to help its digestibility for the reader, it has been published in four parts.

Part 1 – The Role of Renewable Energy

The first article, will critically review the options available for zero carbon energy production using renewables.  

Part 2 -Energy storage

In part 2 the need for backup power is explained when renewable outputs fall and sufficient energy storage is not available.  Various means of storing energy are considered and discussed. 

Part 3 - Nuclear Power and the Reduction of Carbon Dioxide Emissions

In order to give some background before dealing with more recent designs in part 4, in this article the most common types of nuclear reactors currently in service are discussed and their disadvantages highlighted.

Part 4 – Safer Nuclear Power Using Molten Salt andThorium Reactors

The fourth part will expand on the opportunities offered by some more recent nuclear technologies, for much cheaper and safer nuclear power from reactors.  These also generate much less waste, or can even burn waste from earlier generations of reactors.

Part 1 – The Role of Renewable Energy to Combat Climate Change

So if reducing to a minimum carbon dioxide emissions from the burning of fossil fuels is necessary to mitigate the effects of climate change, the questions which remain to be settled are how is this to be done and what will replace fossil fuels.

Tricastin nuclear power station and a wind turbine 

Whilst we can make some progress within developed economies by improvements in efficiency, conservation and demand management, the net result of these measures will be grossly insufficient to counter increasing global demand arising from the legitimate requirement for more energy from developing economies. In this video “The Magic Washing Machine” by Hans Rosling (now sadly deceased) he explains why we in the developed world have no right to tell people in developing economies that they can’t use more energy because of Climate Change, since it’s a major key to lifting poor people out of poverty.

The role of renewables
So as well as conservation measures what is the best way forward? Clearly renewables have a significant part to play in the future of energy production, and they are getting cheaper, but many are still being subsidized and, in common with other energy production technologies, they are not without an impact on the environment.

Global primary energy by source
Primary energy is an energy form found in nature that has not been subjected to any human engineered conversion process. It is energy contained in raw fuels, and other forms of energy received as inputs to a system. Primary energy can be non-renewable or renewable.
Where primary energy is used to describe fossil fuels, the embodied energy of the fuel is available as thermal energy and around 70% is typically lost in conversion to electrical or mechanical energy. There is a similar 60-80% conversion loss when solar and wind energy is converted to electricity, but today's UN conventions on energy statistics counts the electricity made from wind and solar as the primary energy itself for these sources.

The following graphic shows the global primary energy consumed for all purposes including electricity generation. Energy generated from nuclear, hydropower, biomass and other renewables is directly measured as electricity outputs whilst coal, oil and gas need efficiency factors to be applied when they are used for electricity generation, as opposed to industrial process heat or to power vehicles. The vertical axis is in Mega Tonnes of Oil Equivalent Mtoe.





The proportion of carbon free energy i.e. renewables, biomass, hydro and nuclear, is projected in 2030 to be only 20.5% of total primary energy consumed. So, to replace the other 79.5% of primary energy from fossil fuels, an enormous investment in energy from carbon free sources, of all types, is therefore required to meet decarbonization targets and it was needed yesterday!

Biofuels
Except in particular locations bio-fuels are heavy consumers of agricultural land and are unlikely to provide more than marginal amounts of electricity on a global scale but they have a role to play. In Brazil, for example, they are successfully replacing fossil fuels for vehicles with blends of gasoline and ethanol derived from sugar cane. Biodiesel, in various blends, is established in North America and Europe. Biofuels are being encouraged by the EU, but there are concerns that by displacing food production from agricultural land and clearing forests, which are net absorbers of CO2, the production of biofuels could actually release more carbon dioxide than they save.

Tidal power
Tidal power could also contribute more to renewable energy production, and some sites have been in operation since the 1960's. Tidal power generation is, of course, very predictable and could remove much of the need for back up fossil fuel generation for other less predictable renewables, but tidal barrages and lagoons have an impact on ecosystems and the energy generated is on a lunar cycle, which does not coincide with diurnal demand.

Submerged tidal turbines
Submerged turbines placed in locations where currents are created by tidal flows are another possible source of tidal power. Studies are ongoing but environmental impacts are likely to be much less than tidal barrages.

Wave power 

Wave power is a source of renewable energy which could be further developed and wave farms have been installed in a number of coastal locations. Currently the largest operational wave farm has a capacity of 2.4MW and most are in the fraction of a MW range. The graphic below shows the potential in terms of kW/m for the world's oceans and it’s clear that some locations, such as the North Atlantic and Northern Pacific are potentially much more productive than others.

Hydro-electricity
Hydro electricity has, along with nuclear and wind, one of the lowest rates of carbon dioxide generated at 18.5g CO2 per kWh. What’s more it is dispatchable power which can be rapidly varied to suit the demand and compensate for variable generation from wind and solar PV. It’s therefore an attractive investment for governments to make.

Hydropower in Europe

As of 2020 in Europe there were:-

254 GW of installed generation capacity,
55 GW of pumped storage capacity and
676 TWh of electricity were generated in the year representing 13% of total European electricity generation.

During the year 2020, 3GW of capacity were added across the European region, made up mainly by new hydropower plants commissioned in Turkey and other additions in Norway and Albania. Generation from hydropower was almost 4 per cent higher in 2020 than the previous year, owing largely to increased production in the Nordics and Iberia.

Adding major amounts of capacity in Europe involves damming rivers and creating lakes and because there are few “natural habitat-rich” rivers left, this is controversial and unpopular with some environmentalists.

Hydropower internationally
Installed global hydropower capacity rose by 1.6 per cent to 1,330 gigawatts (GW) over the past year 2020 and generated a record 4,370 terawatt hours (TWh) or 19% of world consumption.

During 2020, hydropower projects totalling 21 GW were put into operation, up on 2019’s 15.6 GW. Nearly two-thirds of this growth came from China, which saw 13.8 GW of new capacity. Among other countries that added new capacity, only Turkey (2.5 GW) contributed more than 1 GW.

Wudongde in operation

The single biggest project was Wudongde in China, which put eight of its 12 units online, adding 6.8 GW to the Chinese grid. The remainder are expected to be commissioned in 2021.

China remains the world leader in respect of total hydropower installed capacity with over 370 GW. Brazil (109 GW), the USA (102 GW), Canada (82 GW) and India (50 GW) make up the rest of the top five. Japan and Russia are just behind India, followed by Norway (33 GW) and Turkey (31 GW).

Nevertheless the International Hydropower Association in their 2021 Status Report states that much faster growth is necessary:

Quote <<to limit dangerous global warming and achieve net zero by 2050, the International Energy Agency (IEA), however, says the water power sector will need to double in size to 2,600 GW. This equates to building the same amount of capacity in the next 30 years as was built in the last 100 years.

“At the present rate of hydropower development, the global energy pathway to net zero emissions will not be realised,” warn IHA President Roger Gill and IHA Chief Executive Eddie Rich in the report’s foreword. “This is a wake-up call for policy-makers, hydropower developers and project financiers and provides clarity for the public.

“Investment in sustainably developed and responsibly operated hydropower is essential to support the massive expansion of variable renewables like wind and solar. However annual growth rates of 1.5 to 2 per cent cannot meet the doubling of installed capacity proposed by the International Energy Agency to achieve net zero by 2050.”

According to the report, the Covid-19 crisis has further underlined how the power system flexibility provided by hydropower is now a prerequisite for the clean energy transition. Hydropower’s critical role was illustrated by a recent near blackout incident in Europe in January 2021. >> Unquote.

The emphasis on using hydropower, which is quickly increased or reduced, to support grid power systems having an increasing proportion of variable renewables is enlightening and significant.

Geothermal
There are geothermal power installations of 10MW capacity or more on 72 sites in 16 countries with a total installed electrical output capacity of 10.9 GW. This is proven technology which has been in operation for decades and the total output is equivalent to about 18 typical coal fired power stations. There are almost certainly more opportunities to expand the output of geothermal power and, as carbon reduction policies begin to harden, more plants will be built, but on a worldwide scale its contribution to reducing fossil fuel use will not be very significant.

Wind
Wind power has expanded rapidly in recent years and in 2020 reached 743 GW of installed capacity worldwide. 

Quoting from the Global Wind Energy Council, << 2020 was the best year in history for the global wind industry with 93 GW of new capacity installed – a 53 per cent year-on-year increase – but this growth is not sufficient to ensure the world achieves net zero by 2050. The world needs to be installing wind power three times faster over the next decade in order to stay on a net zero pathway and avoid the worst impacts of climate change.....

......Today, there is now 743 GW of wind power capacity worldwide, helping to avoid over 1.1 billion tonnes of CO2 globally – equivalent to the annual carbon emissions of South America.

Yet, as the clean energy technology with the most decarbonization potential per MW, the report shows that the current rate of wind power deployment will not be enough to achieve carbon neutrality by the middle of this century, and urgent action must be taken by policymakers now to scale up wind power at the necessary pace.>> Unquote.

There is, however, an element of misleading “sales talk” in these figures. The capacity factor of a wind turbine is its average power output divided by its maximum power capacity. On land, capacity factors range from 0.26 to 0.52. In the U.S. the fleet wide average capacity factor was 35%, so applying this to the global total of 743 GW would give an equivalent electrical output of only 260 GW or about a third of the installed capacity. 

Whilst one can understand the Global Wind Energy Council’s enthusiasm for their technology, it would be better for them to be more honest and realistic, and to quote the total energy generated as TeraWatthours (TWh) instead of talking up generation capacity! As a result one has to question their calculations in general and specifically their assumption that wind power is the only option. They also make no reference to its variability and the need to have backup generation available when wind power reduces unexpectedly.

Nevertheless, on an international scale, one can expect wind power to represent a larger and growing proportion of energy supplies.

Solar Photo-Voltaic

Power generation from solar photo-voltaic globally is estimated to have increased by 22% in 2019, to 720 TWh. With this increase, the solar PV share in global electricity generation is now almost 3%. In 2019, PV generation overtook bio-energy and is now the third-largest renewable electricity technology after hydropower and onshore wind.Solar PV generation rose by 22% in 2019

Quoting from the International Energy Alliance June 2020 report 

<< Solar PV electricity generation increased by 131 TWh globally in 2019, to account for 2.7% of the electricity supply. This growth was significantly lower than in 2018, however, because global solar PV capacity additions stalled in 2018 and China’s deployment further contracted in 2019.

From left to right solar PV additions - years 2017-2019

In China, solar PV capacity additions slowed for the second year in row to 30.1 GW in 2019. This expansion is significantly lower than the 53.1 GW in 2017, when the government phased out feed-in tariffs and introduced deployment quotas (in June 2018) to control costs and tackle grid integration challenges. Overall, this policy shift is expected to make solar PV technology more cost-competitive within and outside China, leading to more sustainable development over the longer term. A large number of subsidy-free projects were already in development in multiple provinces in 2019.

Solar PV generation rose sharply in Southeast Asia, driven by a surge in new capacity in Viet Nam from 0.1 GW to 5.4 GW. Capacity additions increased in the United States, the European Union, Latin America, the Middle East and Africa, which together compensated for the slowdown in China, resulting in a record year for PV deployment – 109 GW were installed in 2019.

Solar PV is well on track to reach the Sustainable Development Scenario (SDS) level by 2030, which will require electricity generation from solar PV to increase 15% annually, from 720 TWh in 2019 to almost 3 300 TWh in 2030.>> Unquote.

Land area
Electricity generation from wind and solar energy is based on diffuse energy sources and on-shore based wind power is consequently land hungry. The graphic below illustrates the areas required for different energy generating sources for a capacity of 1000MW (1GW). The units are in square miles. To generate 1GW from wind would require about 300 square miles and from solar about 60 square miles.

In contrast fossil fuel power plants, and those using nuclear energy, are burning energy dense substances and so require only about 1 square mile. In terms of area, a gas fired plant would be comparable with a nuclear power station and a coal fired plant would be a little bigger due to the space required for stockpiling coal and ash.
In Europe, where most non-urban land is already farmed, I question the overall viability and acceptability of covering fields with solar panels. Near us, in South West France, someone has done just that on an area of land that we used to visit each spring to hear nightingales and look at orchids.

Offshore wind
Offshore wind turbines like the Dogger Bank, Wind Farm in the North Sea, have the advantage of not requiring land which could be used for other purposes although, as is reported from the USA, conflicts with fishing industries due to the presence of underground cables are likely.

Offshore wind turbines cost twice as much to install but they are also are more productive since there's almost always more wind off-shore than on land. It follows that countries with long coast lines in comparison with their land area, like the UK, are favourably placed to benefit from off-shore wind power but other countries, don’t have the same opportunities. 

Floating turbines would be able to take advantage of the higher wind velocities further out to sea if they are able to overcome disadvantages due to cost.

The energy transition and mineral realities

There are other real problems with the model currently being pursued by governments to achieve the transition to sustainable carbon emission free energy.

Wind turbines, solar photo-voltaic  and electric vehicles all need minerals, like lithium and rare earth metals, which require mining and processing with their associated environmental and energy costs. This often overlooked aspect of the rapid expansion of the production of these materials is dealt with in detail by Mark Mills in this well researched video.

Variability of wind and solar
Wind power installations are normally expected to produce electricity 30-50% of the time depending on their location, but output is variable over both short and long term timescales. 

The daily mean wind power output for Great Britain during the summer of 2018.
based on data from  www.gridwatch.templar.co.uk

The variability of energy production by location can be an advantage since, if the grid network is sufficiently extensive, having installations in a diversity of locations can result in a degree of smoothing of output power levels.

On dull overcast days, however, solar photovoltaic (PV) power can be largely unproductive, especially in northern latitudes. So when demand peaks on cold winter evenings when there is no sunlight, if there is also no wind, these sources will not supply power.

Solar photovoltaic panels produce most efficiently in hot sunny places, like sparsely inhabited deserts. In certain places, if geo-political constraints involving distance and international borders can be overcome, it may be an economic proposition to generate solar power in one country and transfer it to another. Long transmission lines, with their associated costs and losses (in the USA in 2007 transmission losses were estimated at 6.5%), would then be needed to deliver the power to centres of population.

High Voltage DC lines have been used in some long distance situations. These have the advantage that the capacitance of the line and hence its charging current is no longer a length limiting consideration as it is with alternating current systems. One of the disadvantages is that DC voltages cannot be easily reduced by transformers without first utilizing inverters, with their associated costs and efficiencies, to recreate alternating current.

Dispatchable power
So both solar and wind power are, by their nature, highly variable and rarely provide continuous reliable output. In almost all electricity supply grids at present there is no significant storage capacity so, to meet the varying demand from consumers, electricity utility operators therefore have to schedule the right mix of flexible and inflexible power generation capacity from different types of generators. As part of the day to day management of the grid, this requires them to predict the weather conditions and hence the output from renewables. If there is an unpredictable drop in output from renewables, then flexible generation capacity must be very quickly brought on line. Electricity from flexible sources, known as “dispatchable power”, commands a much higher price in wholesale electricity markets than that from inflexible base load plants, so getting this right is therefore important for both utility companies and consumers. This paper from the US National Renewable Energy Laboratory explains the problem in detail.

If, as in Germany, there's a law forcing utilities to accept energy from renewables as a priority then, as the proportion of total generating capacity that wind and solar power provide increases, there will be an increasing need to maintain backup power supplies, in the form of spinning reserves, with their associated costs and energy consumption. If not the system would become unstable and power cuts would result.

The energy transition and mineral supply

There are other real problems with the model currently being pursued by governments to achieve the transition to sustainable carbon emission free energy. Wind turbines and solar photo-voltaic both incorporate minerals and energy for their manufacture as do lithium ion batteries. The expansion of supply necessary to satisfy the demand created by a rapid transition to these technologies will require enormous increases in mining and processing with their associated environmental and energy costs. This video by Mark Mills gives a detailed examination of this often overlooked aspect of the energy transition.

Grid scale energy storage
In effect, without grid scale energy storage, to satisfy the demand when renewables can't, there will be a limit to the overall proportion of electricity production that can be provided by these non-dispatchable sources. At present grid scale storage is minimal so gas fired turbines are kept spinning at low power, in anticipation of a requirement for bringing higher outputs on line very rapidly.

The next article will deal with some of the many and varied ways of storing energy.

Part 2 - Energy Storage

In Part 1 - The Role of Renewable Energy, I discussed various options for low carbon, or carbon free, energy generation. I concluded that, unless grid-scale energy storage is available, the variability of the most rapidly expanding renewable energy sources, i.e. wind and solar PV, limits their penetration into electricity generation and distribution systems. So what options are available for large scale energy storage?

There are many ways of storing and recovering energy. For electricity the one we are most familiar with is the use of batteries.

Battery storage
The following graphic, which plots energy density in MJoules/litre against MJoules/kg, puts into context the energy density of Lithium Ion and Zinc-Air batteries relative to other substances. The significance of energy density is that gasoline, for example, effectively stores about 50 times more energy per kg than lithium ion batteries and so is a much more portable energy source. This is important for powering aircraft and heavy vehicles.



As a result of its use in electric vehicles, battery storage technology is developing and getting cheaper; but currently batteries are still expensive, have low energy densities and a limited life. In addition as the demand for batteries increases there will be issues to face regarding the price and availability of the minerals which they need for their manufacture. According to Mark Mills in the video above (30:20) changes to the battery chemistry will not fundamentally improve this situation.

In my view both energy density and longevity would need to improve significantly before the use of batteries to smooth out variable production from renewables on time scales, of say 4 to 12 hours or more, would become economic on a grid scale. There are, nonetheless, many battery storage schemes planned or under construction in the US and internationally.

The planned UK scheme at London Gateway, Thurrock, Essex has a peak output of 320MW and a storage capacity of 640MWh. Thus, if the batteries can tolerate 100% discharges, it has a theoretical run time at maximum output of 2 hours but it’s difficult to know what proportion of connected demand this represents.

Compare this to the proposed 3.6GW Dogger Bank Wind Farm in the North Sea, which is being developed in three phases of 1.2GW each, and it’s clear that Battery Storage projects are a long way from acting as medium term backups to Wind Power Generation. (A Gigawatt is 1,000 Megawats).

There is also a 185 MWh battery installation in operation, the Hornsdale Power Reserve, in South Australia, which has a full output rated at 150 MW. This installation is used for frequency and voltage stabilisation and is very fast acting, being able to put power into the grid in milliseconds, and thus smooth out shocks and transients caused by generation blips and load switching. Using the equipment to support electricity supplies in this way has generated significant savings by driving down the cost of providing fast despatchable power, which is otherwise expensive due to the need to run fossil fuel generators in standby mode. Australia’s electricity supply is heavily dependent on coal fired power stations and it remains to be seen whether the use of renewables like wind or solar, combined with battery storage, can be competitive or even politically palatable.

What can be confidently said is that battery storage is going to become more and more important in supporting supply grids with a high penetration of variable renewables in the future.

Energy storage in molten salt
By heating up a salt until it’s molten, energy can be stored in tanks of the hot liquid salt for later recovery by power generation systems. This has been done on the full scale in several solar power plants using directed mirrors in the USA, Spain, and China.

Andasol solar power plant, Spain

It’s also proposed as an adjunct to high temperature reactors such as the Moltex SSR with GridReserve® and the TerraPower Natrium reactor, so that the stored heat can be used to run generators and provide peak power outputs when required.

Other types of energy storage
Other energy storage systems are being proposed and investigated, and some may be promising in the long term, but most are not yet proven to be economically viable or available for widespread deployment. Some of them are discussed below.

Generation of hydrogen
An interesting example is the proposal to use surplus energy generated by wind and solar, when it’s not required by the grid, to produce hydrogen by electrolysis which can be compressed and stored until it’s used: either to blend into natural gas distribution networks, or to power vehicles and aircraft, or to generate electricity during periods of low output from renewables.

The disadvantage with these concepts is their overall efficiency. For example the efficiency of electrolysis is currently 60-70% and the ongoing conversion back into electricity is 40-60% (depending on the method used). Thus the overall efficiency of the round trip is 24-56%, which is much lower than batteries, and there is also the energy cost of compressing the gas for storage but, providing there are periods of overcapacity of installed renewable electricity generation, the electricity used is effectively free.

Work is ongoing to establish the overall economic viability of hydrogen generation and storage.

Some boiler manufacturers like the UK company Worcester-Bosch are conducting long term research to determine the viability of using hydrogen blended with natural gas in a domestic setting. They have found that blends of up to 20% hydrogen require only minor changes to natural gas boilers.

Hydrogen can cause embrittlement of metals and some types of steel used for high pressure gas distribution pipelines may need to be lined or replaced depending on the steel used. Pipelines made from cast iron, polyethylene and elastomeric polymers are unaffected and so the operators of domestic networks are not at risk of major expenditure.

There are also other ways of generating hydrogen using high temperature chemical reactions that fit very well with new nuclear technologies.

Liquid air energy storage

A further method which is getting serious consideration and development is the use of liquid air as an energy storage medium. Similarly to the production of hydrogen, electricity production from wind and solar would be used to liquefy air at atmospheric pressure and when required it can be evaporated under pressure to drive generators.

A 5MW/15MWh demonstration plant, constructed by Highview Power, has been in operation since 2018 at Pilsworth, Bury, UK. Construction has started on an £85m project at Trafford Energy Park, Manchester, UK, which is due for completion in 2022 and will store 250 MWh of energy. The round trip efficiency of such systems is low at around 25% but this can be enhanced, with the use of a cold store, to 50%. If the facility is located near a source of waste heat like an industrial process or thermal power generation system, the efficiency can be further enhanced, and Highview Power claims 70%, without the need to augment the capital cost with heat recovery systems.

Electric vehicles
Another idea is that, when required, electricity could be fed back into the grid from the batteries in electric vehicles: and therefore at some future date a large battery storage capacity would be available to smooth out shortfalls between generating capacity and demand. Although this Vehicle to Grid concept is now being marketed by Nissan and Ovo, it's unclear how it would be managed on a large scale, but it would probably need an infrastructure that had connection points at the majority of parking places; as well as some form of smart metering that credited the vehicle owner if stored electricity, that had already been paid for, was drawn out of the vehicle's batteries. These connection points, or the vehicles themselves, would also need to be equipped with inverters capable of converting DC battery current into AC power and synchronizing it with the grid. This concept has the attractive characteristic that the extra cost of adding these facilities to the charging infrastructure or the vehicles themselves is marginal.

The transition to electric vehicles, which is happening at a surprisingly fast rate, will make a contribution to the reduction in greenhouse gases from burning hydrocarbon fuels. Even if the electricity to charge vehicle batteries comes from gas-fired power stations there will be some efficiency savings and hence overall less carbon dioxide and nitrogen oxides will be discharged to the atmosphere.

But the requirement to charge an ever growing fleet of electric vehicles will put an increasing burden on the electricity supply network. So, without making any allowances for the higher efficiency of electricity versus gasoline when powering vehicles, for the UK I calculate this will require 7 new power stations to be built each year over the next twenty years.

Total number of litres of road fuel in UK per year    45,000,000,000 l/yr
US EPA says 1 US gallon gasoline is 33.7 kWh        34
1 US gallon is 3.785 litres -                                   3.785l /US gallon
so to replace all road fuel would need                    400,660,501,982 kWh/yr
or per day                                                           1,097,700,005 kWh/d
or an average instantaneous demand of                 45,737,500 kW or 45,737 MW
allow double for peak load                                     91,474 MW
Each medium sized power station gives                  700 MW
so it would need                                                   131 new power stations 
or over 20 years -                                                 7 per year

If anyone feels like checking this calculation they’re welcome!

Pumped hydro

One system that has been proved to be viable for energy storage is pumped hydroelectricity, which has had plants in operation for decades. They require two large lakes, one several hundreds of metres above the other.

Water is pumped up when electricity costs are low and released through turbines to generate electricity when required. Due to pump/turbine efficiencies and the two way conversion, the electricity recovered is only about 70-80% of the electricity input. The geographical opportunities for such installations are few, and so far they have only been used for providing flexible power for relatively short durations at peak times when the feed-in tariff for electricity is high.

An example is Dinorwig power station in North Wales which was started in 1974 and completed in 1984.

There are ten such schemes under construction in Europe totalling 1,339MW of capacity. To put this into context, these schemes would add less than 0.1% of the total energy consumption of the 28 EU countries in 2015 as storage capacity. (This total was 12,609 TWh, equivalent to a continuous consumption of 1.44TW. A Terawatt TW is 1 million Megawatts).

Backup power
Backup power production capacity or energy storage is therefore necessary to supply the demand for energy when wind and solar can’t and, because it takes time to bring generating capacity on line, some backup systems have to be kept running even when the demand is being satisfied by renewables.

The German experiment
Under the German EnergieWende, in which it’s intended to move away from fossil fuels and nuclear power to a low-carbon energy economy, up to 2014 they have been running lignite and hard coal fired power plants to replace the energy generated by nuclear plants which have been taken out of service, and to provide backup to wind and solar. During these years the consumption of gas has also been reduced: so the increase in energy from renewable sources has been offset by the reduction in the least carbon dioxide producing sources i.e. nuclear and gas.



The following graphic shows German energy consumption updated to 2019 and corrected for efficiency. 

This means that the vertical axis depicts the amount of primary energy required to generate the indicated amount of TeraWatt hours of electricity. 

Since 2014 the proportion of coal and nuclear electricity generation has decreased, that of gas and oil has stayed the same, whilst wind power has on the other hand increased. So far so good, but it’s clear that the total output from renewables has a long way to go before it represents a significant proportion of total generation capacity. Furthermore if electricity production is ever to be carbon free then the consumption of oil, coal and gas needs to be reduced to zero.

Coal is the most polluting fuel
Coal, and particularly lignite, is the most polluting of all the fuel options since, due to lower efficiencies, legacy plants produce more carbon dioxide per MWh than other fossil fuels and release, into the environment pollutants: including particulates; sulphur and nitrogen oxides; and ash. Ash contains uranium and is 100 times more radioactive than nuclear waste. It also contains heavy metals which will never decay and become less polluting. This ash is typically dumped or stockpiled with minimal control and has caused serious ash-slides necessitating dangerous clean up work. 

Kingston ash slide Tenessee

Air pollution from burning coal is even more serious because it travels further. If, like me you are old enough, you may remember the acid rain arising from UK coal burning power stations that acidified Scandinavian lakes in the 1980's. 

Heavy fog in the city of Anyang, in the industrial Henan province. Photo: CFP

The horrific air pollution in China also dramatically illustrates the results of burning coal and is responsible for many premature deaths.

Germany has passed a law intended to phase out coal fired power stations by 2038.  This will commit Germany to closing all of its coal and lignite fired power stations, but it will clearly be very difficult to phase out both nuclear and coal fired generation, which together represent more than 50% of current capacity, and replace them with intermittent renewables. It’s not clear how Germany intends to fill the gap that it appears likely to create without a change of policy but it will probably be plugged by burning Russian gas.
In effect the German EnergieWende amounts to an experiment on a national scale.

You can be paid for using electricity!
Another effect of relying more and more on renewables has occurred in Germany on some sunny and windy days. Because German law forces their grid operators to accept renewable energy in preference to that from fossil fuels, and electricity production from fossil fuels cannot easily be ramped down, on occasions the price of electricity has become negative in response to an over-supply, meaning that commercial consumers are being paid to burn more electricity!

But Germany is not alone in this situation. In the UK, where there is a free market for electricity, there have been whole weeks when the day-ahead wholesale price of electricity was negative and on 21st May 2020 it fell to an average over 24 hours of minus £9.92/MWh.

It’s clear that this is a ludicrous waste of an otherwise precious resource that results in some measure from subsidies and, apart from providing windfalls to large industrial users who are able to ramp up their energy consumption, it has no advantages. This energy should be used for other purposes which are viable without continuous power, such as, perhaps, generating hydrogen for storage.

Renewable power alone is not the exclusive answer
My conclusion is that, over any specific 24 hour period, renewables can only satisfy a proportion of the total energy demand on any supply grid and a mix of different generation sources and storage types is necessary,

The next article, Part 3 Nuclear Power and the Reduction of Carbon Dioxide Emissions, advocates the use of nuclear power to secure the base load when wind and solar can’t. 

To enable the reader to contrast the technology of the current fleet of 2nd generation nuclear reactors constructed in the 1960’s and 70’s with the more recent and safer designs, that are explained in part 4 of this series, the next article  goes on to describe what second generation nuclear reactors contain and how they work.