The Anonymous Widower

Alternative Energy Storage Technologies To Challenge Electrochemistry

The title of this post, is the same as that of this article on Battery and Energy Storage Magazine.

It gives a good summary of two energy storage system; Highview Power and Gravitricity, that I rate highly promising.

It also gives details of a Danish system called Stiesdal Storage Technologies, which is developing a hot rocks energy storage system.

The article says this about the system.

The pumped-heat ESS uses pea-sized crushed basalt, rock in insulated steel tanks with the stored energy released by turbine.

SST CEO Peder Riis Nickelsen said: “The cost of crushed stone is at a totally different level per unit of energy than practically any other material for energy storage. Our charging and discharging system can utilise well-known technologies that have been applied for a century within other industries and are well-suited for mass production.”

The cost of materials is estimated to be €10 ($12) per kWh.

The first demonstration project, a 1-2MW, 24h capacity unit, will be installed at a power plant in Denmark next year, and will operate commercially.

This page on the Striesdal web site, explains the technology.

It sounds like the system uses very similar principles to Siemens Gamesa ETES, with a different heat storage medium.

Conclusion

At my last count, there now appears to be upwards of half-a-dozen viable alternatives to chemical batteries and traditional pumped storage. Some of the technologies are also backed, by large companies, organisations and countries, who can afford to take a long-term view.

I hope those, who claim that renewables will never power the world, have at least got the recipe for the cooking of humble pie ready.

April 30, 2021 Posted by | Energy, Energy Storage | , , , , | Leave a comment

Malta Inc Energy Storage Explained

Malta Inc first came to my notice in 2018 and I wrote Gates Among Billionaires Backing Alphabet Energy Spinoff.

But I couldn’t find much information at the time, but they now have a web site that gives a good explanation.

This page on the web site is entitled Our Solution.

This infographic from the web page, lays out the key features.

This sentence outlines the method of operation.

The Malta energy storage system takes electricity, converts and stores that electricity as heat, and then converts it back to electricity to be redistributed on the electric grid. In charge mode, the system operates as a heat pump, storing electricity as heat in molten salt. In discharge mode, the system operates as a heat engine, using the stored heat to produce electricity.

The operation is explained in five stages.

  1. Collects – Energy is gathered from wind, solar, or fossil generators on the grid as electrical energy and sent to Malta’s energy storage system.
  2. Converts – The electricity drives a heat pump, which converts electrical energy into thermal energy by creating a temperature difference.
  3. Stores – The heat is then stored in molten salt, while the cold is stored in a chilled liquid.
  4. Reconverts – The temperature difference is converted back to electrical energy with a heat engine.
  5. Distributes – Electricity is sent back to the grid when it is needed.

Note.

  1. The operation of the system is based on well-understood thermodynamic principles.
  2. Entergy is stored as both heat and cold.
  3. It provides several hours of energy storage.
  4. Systems are built using standard components, that are readily available.

In some ways the Malta Inc PHES is based on similar principles to Highview Power’s CRYOBattery and Siemens Gamesa’s ETES.

Conclusion

This is a company to watch, as they seem to have got the technology right.

February 25, 2021 Posted by | Energy, Energy Storage | , , | 2 Comments

Spanish Govt Approves Energy Storage Strategy, Sees 20 GW In 2030

The title of this post, is the same as that of this article on Renewables Now!

This is the introductory paragraph.

The Spanish government on Tuesday approved the energy storage strategy, targeting some 20 GW of storage capacity in 2030 and reaching 30 GW by 2050 from today’s 8.3 GW.

How will Spain increase their storage capacity?

Pumped Storage Systems

Spain already has a couple of large pumped storage systems.

The La Muela II Pumped Storage Power Station

The La Muela II Pumped Storage power station is based on the Cortes-La Muela Reservoir

This Google Map shows the dam.

In terms of generating capacity, it is about the same size as Dinorwig power station in Snowdonia., which is the UK’s largest pumped storage power station.

The Aldeadávila Dam

The Aldeadávila Dam is a 1243 MW hydro-electric power station with a pumped storage addition on the River Douro between Spain and Portugal.

This Google Map shows the dam.

It certainly looks like a place to visit.

Both these pumped storage station seem to have been converted from earlier hydro-electric power stations.

I wouldn’t be surprised to learn, that the Spaniards, were going to increase their number of pumped storage power stations.

  • Spain certainly has the mountains, with big rivers running through!
  • Bolarque dam already uses pumped-storage techniques.

Are there any other existing hydro-electric power stations in Spain, that can be converted to pumped storage or be upgraded?

Concentrated Solar Power

Spain has around thirty concentrated solar power or CSP power stations, either in operation, under construction or planned.

Some also store electricity as heat.

Spain is not short of sun.

Spain is considered a world leader in this technology.

This Google Map shows the Andasol solar power station.

The specification includes.

  • It uses technology called a parabolic trough.
  • A nameplate capacity of 149.7 MW
  • A capacity factor of 37.7 %
  • Annual net output of 495 GWh
  • a storage capacity of 1.123 GWh
  • The energy storage is based on a mixture of potassium and sodium nitrates.
  • The power station takes up an area of six square kilometres.

Will Spain build more of these CSP power stations or add energy storage to some of the existing stations?

Batteries

The article has this sentence.

the government wants to add large-scale batteries, behind-the-metre batteries — minimum 400 MW in 2030 — and make the most of the vehicle-to-grid technology, according to the document.

It should be noted that Spain has installed capacity of over 25 GW of wind power, according to this article on Wikipedia, which is entitled Wind Power In Spain.

These are some points from the article.

  • Spain has a lot of indigenous wind turbine manufacture.
  • The Spanish wind-power industry employs upwards of 60,000 people.
  • A central control centre for Spanish wind power needs to be developed.
  • There is little opposition to onshore wind, although perhaps somewhat surprisingly, there is some opposition to offshore wind.

After reading what Wikipedia had to say, it appears to me, that Spain needs a ;pt of batteries to support all these wind turbines.

The world’s second largest wind-turbine manufacturer is Siemens Gamesa, who are Spanish-based.

Siemens Gamesa have an innovation storage battery based on hot volcanic rock, which I wrote about in Siemens Gamesa Begins Operation Of Its Innovative Electrothermal Energy Storage System.

This gives a brief description of the pilot plant.

The heat storage facility, which was ceremonially opened today in Hamburg-Altenwerder, contains around 1,000 tonnes of volcanic rock as an energy storage medium. It is fed with electrical energy converted into hot air by means of a resistance heater and a blower that heats the rock to 750°C. When demand peaks, ETES uses a steam turbine for the re-electrification of the stored energy. The ETES pilot plant can thus store up to 130 MWh of thermal energy for a week. In addition, the storage capacity of the system remains constant throughout the charging cycles.

It was taken from this press release from Siemens Gamesa.

This page on the Siemens web site gives the nominal output of the system as 30 MW.

So it would need just over a dozen systems like these to perhaps be strategically-placed near large wind farms to meet Spain’s target of 400 MW of energy storage.

Highview Power’s liquid air systems would be another possibility, but I doubt, they’d perform as well in the heat of Spain, as a system based on hot rocks.

Conclusion

Spain’s plan seems achievable and could create a lot of employment.

It also seems to me, that their natural resources of mountains, big rivers and lots of sun are a great help.

 

 

 

February 11, 2021 Posted by | Energy, Energy Storage | , , , , , | 3 Comments

Battery Life: The Race To Find A Storage Solution For A Green Energy Future

The title of this post, is the same as that of this article on the Financial Times.

It is a long article, that gives a good review of the technologies available to store energy from wind and solar power.

It gives a lot more details and an image of the Siemens Gamesa hot rock energy storage system in Hamburg.

  • It uses a thousand tonnes of volcanic rock.
  • It can store 130 MWh of electricity.

The system has apparently been designed to re-use the turbines from closing coal-fired power stations, which is an innovative idea.

 

November 23, 2020 Posted by | Energy Storage | , , , | Leave a comment

Will BALDIES Save The World?

I just had to use this new acronym, I’ve just found on the Internet.

BALDIES are Build-Anywhere-Long-Duration-Intermittent-Energy-Storage.

June 19, 2020 Posted by | Energy Storage | , , , | 2 Comments

UK’s Largest Solar Park Cleve Hill Granted Development Consent

The title of this post, is the same as that of this article on Solar Power Portal.

These are the two introductory paragraphs.

Cleve Hill Solar Park, set to be the largest in the UK, has been granted development consent by the energy secretary.

The colossal 350MW project will include 880,000 panels along with battery storage, and sit just one mile northeast of Faversham, in Kent, situated close to the village of Graveney.

Other points from the article.

  • Cleeve Hill Solar Park is a £450million project.
  • It is the first solar project to be considered a Nationally Significant Infrastructure Project.
  • It is being developed as a joint venture between Hive Energy and Wirsol.
  • It is due to be operational by 2022.
  • To complete the project 700 MWh of energy storage will be added later.

The article also contains this quote from Solar Trade Associations chief executive Chris Hewett.

Solar has a significant role to play in boosting the economy in the wake of the coronavirus crisis. With the right policies we can expect to see an 8GW pipeline of solar projects unlocked and rapidly deployed, swiftly creating a wealth of skilled jobs and setting us on the path towards a green recovery.

8 GW of intermittent energy will need a lot of storage.

As Cleeve Hill’s developers are planning to provide 700 MWh of storage for 700 MW of solar panels, it would appear that 8 GW of solar panels could need up to 16 GWh of energy storage.

As our largest energy storage system is the pumped storage Electric Mountain in Snowdonia with a capacity of 9.1 GWh and most of the large solar developments are towards the South of England, the UK needs to develop a lot more energy storage, where the solar is generated and much of the energy is used.

I can see the following environmentally-friendly developments prospering.

  • Highview Power‘s CRYOBattery, which uses liquid air to store energy. Systems have a small footprint and up to a GWh could be possible.
  • Electrothermal energy storage like this system from Siemens.
  • Using electrolysers from companies like ITM Power to convert excess energy into hydrogen for transport, steelmaking and injecting into the gas main.
  • Zinc8‘s zinc-air battery could be the outsider, that comes from nowhere.

Developers could opt for conservative decision of lithium-ion batteries, but I don’t like the environmental profile and these batteries should be reserved for portable and mobile applications.

Floatovoltaics

One concept, I came across whilst writing was floatovoltaics.

The best article about the subject was this one on Renewable Energy World, which is entitled Running Out of Precious Land? Floating Solar PV Systems May Be a Solution.

A French company call Ciel et Terre International seem to be leading the development.

Their web site has this video.

Perhaps, some floatovoltaics, should be installed on the large reservoirs in the South of England.

  • The Renewable Energy World article says that panels over water can be more efficient due to the cooling effect of the water.
  • Would they cut evaporative losses by acting as sunshades?
  • As the French are great pecheurs, I suspect that they have the answers if anglers should object.

This Google Map shows the reservoirs to the West of Heathrow.

Note.

  1. Wraysbury Reservoir has an area of two square kilometres.
  2. King George VI Reservoir has an area of one-and-a-half square kilometres.
  3. Using the size and capacity of Owl’s Hatch Solar Farm, it appears that around 65 MW of solar panels can be assembled in a square kilometre.
  4. All these reservoirs are Sites of Special Scientific Interest because of all the bird life.
  5. Heathrow is not an airport, that is immune to bird-strikes.

Could floatovoltaics be used to guide birds away from the flightpaths?

Incidentally, I remember a report from Tomorrow’s World, probably from the 1960s, about a porous concrete that had been invented.

  • One of the uses would have been to fill reservoirs.
  • The capacity of the reservoir would only have been marginally reduced, as the water would be in the voids in the concrete like water in a sponge.
  • Soil would be placed at the surface and the land used for growing crops.

I wonder what happened to that idea from fifty years ago!

June 5, 2020 Posted by | Energy Storage | , , , , , , , , , | Leave a comment

Siemens Gamesa Begins Operation Of Its Innovative Electrothermal Energy Storage System

The title of this post, is the same as that of this press release from Siemens Gamesa.

This is the introductory paragraph.

In a world first, Siemens Gamesa Renewable Energy (SGRE) has today begun operation of its electric thermal energy storage system (ETES). During the opening ceremony, Energy State Secretary Andreas Feicht, Hamburg’s First Mayor Peter Tschentscher, Siemens Gamesa CEO Markus Tacke and project partners Hamburg Energie GmbH and Hamburg University of Technology (TUHH) welcomed the achievement of this milestone. The innovative storage technology makes it possible to store large quantities of energy cost-effectively and thus decouple electricity generation and use.

This second paragraph gives a brief description of the system.

The heat storage facility, which was ceremonially opened today in Hamburg-Altenwerder, contains around 1,000 tonnes of volcanic rock as an energy storage medium. It is fed with electrical energy converted into hot air by means of a resistance heater and a blower that heats the rock to 750°C. When demand peaks, ETES uses a steam turbine for the re-electrification of the stored energy. The ETES pilot plant can thus store up to 130 MWh of thermal energy for a week. In addition, the storage capacity of the system remains constant throughout the charging cycles.

This system is a pilot plant and will test the system thoroughly.

They state that the long term aim is to store energy in the gigawatt range and be able to provide the enough power for the daily electricity consumption of around 50,000 households.

The method of energy storage would appear to be inherently simple.

  • Heat rocks to a high temperature using a gigantic electric heater and blower.
  • Use the heat when required to boil water to create steam.
  • Pass the steam through a conventional steam turbine.

I can envisage a clever computer system, controlling the hot air and water flows into the vessel to get the correct level of steam out, as needed for the amount of electricity required.

I suspect the biggest problem is where do you keep a thousand tonnes of hot rock?

The answer is given in this article on the American Society of Mechanical Engineers, which is entitled Heated Volcanic Rocks Store Energy.

This paragraph describes the storage.

A key finding from an earlier, smaller project proved greater efficiency of a round shape for the container holding the rock. It has an increasing diameter on both ends, where inflow and outflow openings are located. It has a total content of 800 cubic meters of rock with a mass of 1,000 tonnes, covered with a one-meter-thick layer of insulation.

I estimate that the diameter of a 800 cubic metre rock sphere would be just 11.4 metres, so perhaps around fourteen with the insulation.

The sphere would need to be a pressure vessel, as it would contain high-pressure steam.

The process looks to be simple, efficient and scalable.

The article also makes the following points.

  • Eighty percent of the components are off-the-shelf.
  • There are no hazardous materials involved.
  • High efficiencies are claimed.
  • Siemens Gamesa are aiming for a 1 GWh system.
  • The German government has provided development funds.

It is being built on the site of an old aluminium smelter, so I suspect, the site has good connections to the electricity grid.

In the early 1970s, I was involved in the design and sizing of chemical plants for ICI. In one plant, the process engineers and myself proposed a very large pressure vessel, that would have been larger than the one, Siemens Gamesa are using in Hamburg. But then the domes of pressurised water reactors, like this forty-six metre diameter example at Sizewell B are even larger.

 

I very much believe, that design and construction of the pressure vessel to hold the hot rocks for Siemens Gamesa’s system could have been performed by the team I worked with in 1972

How Big Would The Sphere Be For A One Gigawatt-hour System?

  • The current pilot system has a 130 MWh thermal capacity and uses a thousand tonnes of volcanic rock.
  • The rock occupies 800 cubic metres.

I estimated that the pressure vessel with insulation could have a diameter of fourteen metres.

A system with a 1 GWh thermal capacity would be 7.7 times larger.

  • It would need 7,700 tonnes of volcanic rock.
  • The rock would occupy 6,160 cubic metres.

I esimate that the pressure vessel with thermal insulation would have a diameter of twenty-five metres.

How Much Power Could Be Stored In A Sizewell B-Sized Dome?

Out of curiosity, I estimated how much power could be stored in a pressure vessel, which was the size of the dome of Sizewell B power station.

  • The dome would have a diameter of forty-two metres if the insulation was two metres thick.
  • This would store 39,000 cubic metres of rock.
  • This would be 48,750 tonnes of rock.

Scaling up from the pilot plant gives a 6.3 GWh thermal capacity.

I would suspect that Siemens know an engineer, who has worked out how to build such a structure.

  • A steel pressure vessel wouldn’t be any more challenging than the dome of a pressurised water reactor.
  • It would be built in sections in a factory and assembled on site.
  • Rock would probably be added as the vessel was built.

I can certainly see one of these energy stores being built with a multi-gigawatt thermal capacity.

Would This System Have A Fast Response?

Power companies like power stations and energy storage to have a fast response to sudden jumps in demand.

This section in the Wikipedia entry for Electric Mountain, is entitled Purpose and this is said.

The scheme was built at a time when responsibility for electricity generation in England and Wales was in the hands of the government’s Central Electricity Generating Board (CEGB); with the purpose of providing peak capacity, very rapid response, energy storage and frequency control. Dinorwig’s very rapid response capability significantly reduced the need to hold spinning reserve on part loaded thermal plant. When the plant was conceived the CEGB used low efficiency old coal and oil fired capacity to meet peaks in demand. More efficient 500 MW thermal sets were introduced in the 1960s, initially for baseload operation only. Dinorwig could store cheap energy produced at night by low marginal cost plant and then generate during times of peak demand, so displacing low efficiency plant during peak demand periods.

Given that we are increasingly reliant on intermittent sources like wind and solar, it is surely getting more important to have energy storage with a fast response.

Consider.

  • Gas turbine power stations are very quick to start up, which is a reason why, they are liked by power companies.
  • As Wikipedia says pumped storage systems like Electric Mountain usually have a fast response.
  • Lithium-ion batteries have a very fast response.

I think the Siemens Gamesa ETES system could have a medium-fast response, provided there was enough heat in the rocks to raise steam.

Could This System Be Placed In A Town Or City?

Consider.

  • The system doesn’t use any hazardous materials.
  • The footprint of a 1 GWh system would probably be football pitch-sized.
  • The system could probably be designed to blend in with local buildings.

This picture shows the Bunhill 2 Energy Centre in London, which extracts waste heat from the Underground and uses it for district heating.

When I took the picture, the system wasn’t complete, but it shows how these types of developments can be fitted into the cityscape.

 

 

May 15, 2020 Posted by | Energy Storage | , | 2 Comments