Link to article in PV Magazine Energy Storage

Link to Volkswagen press release

This is not an announcement of future plans or research findings. The construction phase has been completed and the system has been commissioned, meaning it has been tested as ready for operation.

So far the car companies who are in both the battery car business and the commercial stationary battery business include Tesla, BYD, Ford, and Volkswagen. Honda is in the business of solar panels and home batteries.

It may happen that these companies become known as battery companies with vehicle and stationary battery divisions.

In any case, my readers who are project developers should know who they can call to get a manufacturer's application engineers involved in making a proposal to a potential buyer of such a project.

For project developers

• The scope is 20MW and 40 MWh, so this is small by utility standards but large for a commercial building or campus. The batteries would discharge over 2 hours at the 20 MW rate but longer at lower discharge rates. A rate of 10 MW would give 4 hours of electric energy, for example.

• Volkswagen’s battery subsidiary is named PowerCo. This is the name to contact for sales support.

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• Elli is a company with access to wholesale power markets and is providing the power trading service. Link to Elli press release

• No project costs, or financial metrics such as Net Present Value are cited.

• The value of this project is not in energy savings. In fact, a battery is a load while charging and has a Round-Trip Efficiency of 85% to 90%. This battery is a tool for moving electric energy in time and being paid for the service. Batteries are typically charged in the morning when supply is high and wholesale electricity prices are low, and discharged in the afternoon when wholesale prices rise. In a financial analysis the benefits calculation will be centered around the opportunity to buy low and sell high.

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Link to Clean Technica article

Wind-sourced electricity is generated in sparsely-populated areas, many of which are also places were ammonia fertilizer is used.

Ammonia, NH3, can be made using nitrogen from the air and hydrogen, H2, which can be made by the electrolysis of water.

To make ammonia with these inputs you need a processing plant using the Haber process and inputs of electricity and air.

When the electricity input is going to come from variable wind-sourced electricity there are modifications that are made to the processing plant compared to a plant designed with the assumption of a constant input of electricity.

For Project Developers:

• The set of wind turbine and variable energy-ready Haber plants are in use today. This is not an announcement of a laboratory finding.

• Agricultural areas will be the best locations.

• The article does not mention cost of the plant or costs per unit of output.

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Link to article in Energy Connects

Here is a story of a wind farm operator who committed to provide power whether the wind turbines generated it or not. This proved to be inadequate risk management.

By the terms of the Power Purchase Agreement sales contract, the owner was forced to buy electric energy on the spot market, which experienced the price spike in the graph.

The article has details on the Power Purchase Agreement that the parties thought was a win-win business model.

The wind turbines also fell short of the projected quantity of energy available for sale.

My opinion is that wind-sourced electricity is a valuable resource with an input energy that is beyond the war-related price spike of natural gas-sourced that led to financial problems for this wind farm operator. The kinetic energy of the wind has been put to use in windmills and sailing ships for centuries. We now can convert it to electric energy with no need for a fuel supply chain and the points of failure this project encountered when it needed to buy spot market electricity.

I am sure the history of this business venture will be studied for lessons learned. I predict the risks of a shortfall in wind-sourced electricity will be split between the seller and the buyer is a way that puts more risk on the buyer. One party or the other needs to adjust demand and supply until they match.

Here are my suggestions.

The ideal buyer is probably one that can vary its demand and not need either party to procure power on the spot market or provide fossil-fuel generation. Perhaps a pair of buyers could be found where one of them takes the entire role of varying its demand, perhaps a company that makes a seasonal product and stores inventory for later sale.

The ideal seller is perhaps a pair of energy producers, one with fossil-fuel generation and the other with wind farms; perhaps a joint venture for the purpose of selling electricity. The plan for meeting a fixed customer demand by varying the fuel input of the joint venture could cover the issue of wind-sourced electric energy varying with the wind.

Here is the concluding quote from the article.

The location is excellent, said Jakob Norstrom, CEO of Statkraft in Sweden. But when signing a PPA, he struck a note of caution: “It’s important to find the right balance so you don’t promise too much.”

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Link: NRC Press Release on Terrapower

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I have become a skeptic about new nuclear power being a viable business. Part of my skepticism is the track record of slow construction. Another part of my skepticism is the number of licenses an owner must obtain from the Nuclear Regulatory Commission. None of the other sources has a regulatory agency devoted to issuing it licenses. A license is needed for the design, the construction, operation, and disposal of the waste.

I have been a team member on projects where the weekly meetings became strategy sessions on how to get a response from the issuers of permits less complicated than nuclear operating licenses. Multiple people billed time to the job for each meeting and no forward progress was made. The project cost went up but there was no corresponding increase in its value.

President Trump and Secretary Wright have said nuclear is part of our energy dominance plan along with clean coal and natural gas.

I was under the impression this TerraPower project was under construction in Kemmerer, Wyoming. I thought I read repeatedly that the projected date for the first kWh was 2030. I have been stating that as fact in my reporting on electric power from new nuclear plants. I have said it was this project and its 2030 date which was the first.

Here are some quotes from the press release that illustrate the scope of licensing time needed. The emphasis is mine.

• “NRC staff finished their technical review of this new design in less than 18 months.”

• “The staff expects to issue the permit soon.”

• “TerraPower filed the application in March 2024, requesting a permit to build the sodium-cooled, advanced reactor design on a site near an existing coal-fired power plant. The NRC staff accepted the application and began formal review in May 2024.”

• “The 345-megawatt electric (MWe) plant includes an energy storage system to temporarily boost output up to 500 MWe when needed. US SFR Owner would need to submit a separate operating license application, and the NRC staff would need to approve it before the facility could operate.”

If President Trump and Secretary Wright can speed up this process the country will be grateful.

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Source: rondo.com

How can a factory in need of steam take advantage of solar energy?

Heinekin and others are using a refractory brick heat-storage system from Rondo Energy.

An article in Facilities Dive explains the technology and contract.

Link to Facilities Dive article

What project developers should know

• Reporting on emissions for ESG rating is at least part of the goal. Scope 1, 2, and 3 are ESG categories. The article’s headline mentions a plan to decarbonize.

• Here is the scope: “As part of the agreement, EDP will install a 7 megawatt-peak solar plant at Heineken’s Central de Cervejas e Bebidas brewery, which will power Rondo’s heat battery. Rondo’s 100 megawatt-hour battery will convert and store the renewable electricity as high-temperature heat and supply continuous zero-carbon steam for Heineken’s production processes.”

• Renewable energy from the grid is part of the energy supply. “The PPA will provide 25 gigawatt-hours of renewable energy annually, permitting the Dutch brewer to maximize the volume of clean energy available to it, according to EDP.”

• The schedule is to have the system running by April 2027.

• No budget is mentioned, and no simple payback period or other financial metric.

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Click here to read the full article in PV Magazine

This Battery Energy Strorage System (BESS) is in the category Long Duration Energy Storage (LDES).

Here is a quote:

“While lithium-ion batteries are effective for 4-hour shifts, they cannot handle the multi-day storage. Form Energy said its iron-air batteries can store renewables-sourced electricity for 100 hours at system costs competitive with conventional power plants.”

Project developers should know these facts.

• The manufacturer is Form Energy, formenergy.com

• Form Energy is a young company with little track record. I consider them to be in the start-up phase, with the risks that come with new companies and new technologies. Investors, however, are companies with deep pockets.

• Iron-air batteries are less energy dense than lithium ion batteries.

• Iron-air batteries have lower Round-Trip Efficiency. Often in the range of 40% to 60%. The pro forma financial calculations will be far different from those for lithium ion at RTE of 85% to 90%.

• I see only fuel-cost-free solar and wind energy as candidates for the source energy. Wasting energy with a zero marginal cost of kWh energy and kW demand means the energy input cost row is zero in the financial case of using batteries. In the base case of buying energy from the utility the cost of kWh and kW demand will come from a rate tariff or negotiated contract.

• Iron-air batteries are non-flammable.

• Form Energy’s product is designed for 100-hour storage.

• This article does not quote a cost.

• The factory is in the US, in West Virginia. A financial pro forma should include the Domestic Content bonus provided in the Inflation Reduction Act.

• The article does not state the owner but the PPA contract implies it will be Xcel Energy, the local utility company.

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Click here for the ASHRAE Position Document pdf

I am a member of ASHRAE, the professional society for air conditioning engineers. A Life Member actually, a designation you get if you hang around for 30 years.

Carbon dioxide concentration is inexpensive to measure and modern electronic control systems in buildings routinely have carbon dioxide sensors, with the ppm of carbon dioxide used as an input signal to determine the rate of outside air introduced.

In practice, I have typically seen the controls set to some set point value in the range of about 700 ppm to 1000 ppm. Outdoor air dampers are commanded to open when the carbon dioxide level exceeds the set point.

But why was this level chosen?

The link below takes you to a position document approved by the ASHRAE Board of Directors. This position paper is updated on a schedule as new information is discovered. The history of the use of CO2 concentrations in control systems is discussed in Appendix A. The conclusions of a number of studies are compared.

Here is a quote describing the issues discussed in the rest of the paper:

“While these topics have been studied for decades, incorrect application and misinterpretation of CO2 concentration as an indicator of IAQ and ventilation is common in the HVAC industry, research community, and the public. Despite many efforts to address these concerns in standards, guidance documents, technical publications, and conference presentations, significant misunderstanding of the application and meaning of indoor CO2 remains.”

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I was in the commenting section on a blog and I was challenged on several points of my view of energy, one point at a time. I wrote out this response. It includes some of my personal history starting with the oil embargo of 1973.

I wrote:

Here is my view of things.
- I was on the receiving end of an embargo in 1973. It hurt me personally. I was a healthy college student. There were vulnerable people who were hurt worse.
- We all in the US are now on the receiving end of an embargo of rare earths. It hurts. We are trying to be independent in rare earths. I see a direct analogy to being independent of energy suppliers. The sun and wind have no suppliers who can cause us a shortage.
- Depending on suppliers makes you dependent. You give up freedom. Their actual shortages are your shortages. Their imposed shortages on you are your shortages.
- There are things you can do to mitigate the damage.
- I think we should do them.
- When it comes to energy, I have been doing calculations on solar photovoltaics every once in while for over 30 years. Rarely would a customer say the package of hard savings and soft benefits were worthwhile. The prices changed but the decision was always the same. I agreed - in fact that was my advice, just buy electricity from the utility company and buy a diesel backup generator for outages. The return on your investment is below your hurdle rate so far that it would be irresponsible to invest that way as a financial decision.
- One day in 2017, about 10 years ago, I was working in my company's Salt Lake City office and someone who was watching the wholesale price of electricity saw it go negative. He said, "Hey California is paying us to take their electricity!" Wow. My world changed. Energy was now abundant, not scarce. The Energy Crisis was over. It started in the 1970s and ended in the 2010s, about 40 years later. Fuel-cost-free solar power pushed the price negative. Fuel-fed power plants have never done that.
- One day in 2025 at my house in Houston I accepted the offer of a door-to-door solar salesman to calculate a preliminary pro forma financial analysis. I got my utility bills, he ran them through his program, and I found I could break even. My roof was competitive with the entire ERCOT grid. Wow. That meant we were at a turning point. It was possible for me to be a competitor to the utility company. I did not buy any solar panels. My bills are low with Texas' below-average rates and I think 8 years is the upper limit for me to stay in this house.
- I am in touch with a man younger than me whose house is about 20 miles from mine, in ERCOT, who has solar panels on his roof, a battery in his garage, a bigger battery in his car, a contract with a Retail Electricity Provider to buy his excess kWh and a contract with a Virtual Power Plant to buy kW from him at their request. It is all automated but it was a lot of work to get the controls from different manufacturers to communicate with one another. He spent about $40,000 on the solar panels and garage battery. He can afford it, he paid cash, and he sees it as buying several years worth of electricity in advance. He leased the car when it was time to move on from his oldest car. He has not paid a utility bill in over a year since he got this all set up. His motivation is in soft benefits. It was for outage protection after the 2021 freeze and multi-day outage. His neighbors bought gas generators for probably $15,000 and they just sit there earning nothing.
- Solar and wind power are fuel savers that do their thing in generating electricity when the input energy of sunshine and wind are available. They are not dispatchable for use at peak demand, but in places like Texas where the peak demand is on summer afternoons they help in the multi-source solution to meeting the aggregate load.
- A grid needs dispatchable resources; usually natural gas is used. ERCOT does that.
- The biggest energy source in ERCOT, summing up over time, is natural gas. Second is wind. Third and fourth are pretty much a tie between coal and solar. Nuclear is last. This works day after day, for 20 years now.
- ERCOT has five main sources where not too many years ago it had only three. Batteries are dispatchable sources where the energy source is the other sources, but at a different time. They are the sixth source used at peak times. Deep-well geothermal for electricity generation may become the seventh. The character of the grid is changing.
- I watch the ERCOT.com dashboard showing the fuel mix. Can large loads like steel mills be run on solar and wind? Well if they can be run on electricity we often have 20 GW or more of solar and wind power at the same high transmission voltages as every other source. For perspective, the Vogtle nuclear plants in Georgia are 1 GW each. Every day we run Houston, Dallas, Fort Worth, San Antonio, Austin and lots of smaller towns on one-third to two-thirds solar and wind power. My judgement is that large loads are being served now. If steel mills work better on coke, coal, or natural gas they should keep doing it.
- I don't say a grid can be run completely on solar and wind. But that day is coming, at least in certain places. In both the UAE and Saudi Arabia they are building 1 GW power plants with solar as the only energy source. They have a lot of sunshine. Why let it go to waste? The setup is roughly 1 GW of solar panels, the nameplate rating standard in the industry, and 19 GWh of battery capacity. The design is to provide 1 GW constantly, 24/7/365. The cost is $6 per watt, competitive with the cost of other new power plants. I am watching to see if it works.
- Nuclear is great, safe, and produces large quantities of power for a small amount of fuel. The footprint is smaller than solar panels, but also off limits for any concurrent use. I am using 10% nuclear power at my house right now. I am not complaining. The nuclear people are saying Small Nuclear Reactors will be ready in the 2030s. The fusion people say the 2040s. People are building $80 billion in new construction nuclear plants using the Westinghouse design already in service many places. This is a result of an Executive Order. These people are just getting started on new plants of old, proven design. I haven't seen that they have stuck their necks out and predicted a date for their first kWh. Grid operators will blend in their energy when it comes to pass they can produce it. Go ahead, nuclear people. Build some plants and I will be your customer.

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https://www.energy.gov/articles/energy-department-announces-largest-loan-department-history-delivering-over-7-billion

I don’t see how $300 million per year in interest savings on Southern Comany’s books translates to $7 billion savings for consumers, but I guess that is the nature of press releases.

I can calculate a rule of thumb. The $26.5 billion gets us 16 GW of new capacity. That works out to $1.65 billion per GW, or $1656 per MW. My old rule of thumb was $1000 per MW for new generation.

The list looks mostly like routine replacement of capital equipment that will provide no new capacity. Hopefully Southern Company already had a plan for replacement of equipment as it reaches the end of its useful life.

Secretary Wright always emphasizes that a grid’s primary function in his mind is to meet the peak load. He speaks derisively of solar and wind sources of electricity, which save fuel which is needed during times of peak generation if they happen to occur when photons are not available for photovoltaics or wind kinetic energy is not available.

On many summer days photovoltaics produces electricity at the peak in the afternoon. On many winter nights wind energy produces at the peak during the night. In Texas, we credit solar-sourced electricity as the key to getting through the summer of 2025 with no emergencies.

Secretary Wright’s position for electricity emphasizes sources that are dependent on fuel. His position on oil and gas production emphasizes we export it. Many of us who lived through the embargo of 1973 when the US was a buyer of oil think saving fuel is good for national security and serves American citizens well.

It appears to me that battery storage is now been grouped as “firm reliable power” even if solar and wind are left out.

Here is a quote from the press release.

“The two loans will build or upgrade over 16 gigawatts (GW) of firm reliable power to the electrical grid. This includes 5 GW of new gas generation, 6 GW in nuclear improved through uprates and license renewals, hydropower modernization, battery energy storage systems and over 1,300 miles of transmission and grid enhancement projects.

These loans represent the largest government investment aimed at directly lowering consumer energy costs and increasing grid reliability. Once all funds are received through the program, the loans are estimated to reduce Southern Company’s interest expenses by over $300 million per year, helping expedite lower electricity costs for customers.”

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Here are the top 10 importing countries. But who are the manufacturers? TradeImeX has the answer. See below for the summary graph. See the article for details.

Source: https://www.tradeimex.in/

https://www.tradeimex.in/blogs/global-solar-panel-import-data-2024-25-top-importers-by-country

The top manufacturers are:

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Source: The Economist, February 26, 2026

https://www.economist.com/the-americas/2026/02/26/donald-trumps-oil-embargo-reveals-a-solar-boom-in-cuba

Here is a quote from the article:

Yet things are not as bad as they might be, and not only because the island meets 40% of its fuel needs with its own heavy, sulphurous crude. Mr Trump is obsessed with oil, but Cuba has been building out an alternative source of energy supply at record pace: solar panels imported from China. According to Chinese export data compiled by Ember, a think-tank, in the 12 months to April 2025 Cuba’s imports of Chinese solar panels grew by a factor of 34, faster than anywhere else in the world. The island has gone from having almost no solar power a few years ago to levels which help it cope with Mr Trump’s embargo.

One aspect of solar and wind energy I emphasize is its value in national security. It works for all countries, including the United States.

I lived through the oil embargo of 1973. It hurt. I was 250 miles from home on a road trip in my college years and a gas station owner told me he would only sell me two dollars worth of gas, about a quarter tank. I drove the 55 mph speed limit for the several years it was national policy, and 12 states had set their maximum speed limit at 50 mph.

Today’s solar and wind technologies have their roots in the Energy Crisis when national security was a goal of non-fossil fuel generation and energy conservation wherever it could be implemented.

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Image: Grok

Today I was discussing energy sources with a correspondent on X. What started the conversation was a government report which mentioned batteries as a generator.

Not too long ago we had three main sources in Texas. Now we have five. None of them are interchangeable and they all are useful tools for grid operators.

They work together nicely as a system.

The equipment types I mean are:

- Nuclear plants, which go down for a month at a time for refueling.

- Coal plants, which are hard to turn up and down.

- Natural gas plants, of which one style is hard to turn up and down but easier than coal, and the other style which is easy to turn on quickly but is inefficient so the plants usually sit idle just hogging up capital.

- Hydropower, which can be turned up and down but is only located in a few lucky places.

- Solar-sourced electricity, which needs photons for photovoltaics, and varies from a low of no output to a high of so much we don't know what to do with it all.

-Wind-sourced electricity, which needs wind, which works 24/7/365 but varies by geographic location and height above the ground, plus variations in the weather,

-Geothermal-sourced electricity, which runs 24/7/365 but is just getting started as a major source.

- Batteries, which take in electricity when it is most available and inexpensive on the market, and releases electricity when it is most needed and expensive on the market.

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https://www.pv-magazine.com/2026/02/20/rethinking-solar-and-storage-roi-beyond-old-efficiency-assumptions/

Consider this strategy from Sean McPherson. The point is to get the most dollars out of the solar-sourced electricity you have made. Set your modeling program to take advantage of this opportunity.

Benefits and costs:

• The benefit is that you get the most dollar value each day or year.

• The cost is that you need to buy and maintain a battery.

• The soft savings of outage protection is often reason enough for a customer to install a battery and solar panels to charge it. A natural-gas whole-house battery installation might be $15,000 while a battery and solar panels might be $35,000.

• A customer who thinks outage protection is worth $15,000 might also be a person who thinks generating power on the roof is worth $20,000. Your financial analysis for the energy savings potion of the project will have a first cost of $20.000.

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Here is a chart of the planned upcoming additions to the grid for each month of 2026. Projects can be cancelled or reduced in scope but it is unlikely any new ones will be added before the year is out.

Nuclear is getting a lot of publicity as an important technology for our future. I was surprised when I found out that no significant nuclear sources will be added to the grid for a few years. Many are somewhere in the development and approval process so it looks like new nuclear will become a reality. But not in 2026.

The inclusion of battery storage as generating capacity needs some explanation. Batteries provide power to the grid when discharging, but are loads on the grid when charging. Storage in pumped hydro and batteries has the function of moving power in time from when it is most available to when it is most needed. Pumps have an efficiency of about 70%. Batteries have an efficiency of about 90%. When we store electricity we lose some of it to heat and don’t get it all back.

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https://www.energystorages.tech/tesla-completes-worlds-largest-solar-powered-energy-storage-supercharger-station-164-stalls-operating-completely-off-grid.html

Tesla has completed a charging oasis for 164 cars along the main route from Los Angeles to San Francisco. An article in Energy Storages Tech gives an update.

Here is quote:

Charging Performance and User Experience

Each charging stall utilizes Tesla’s latest V4 Supercharger technology, with individual stalls capable of delivering up to 325 kW of power. This means compatible vehicles can add approximately 200 miles (about 322 kilometers) of range in roughly 15 minutes.

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The US Department of Energy has a searchable database of solar arrays with nameplate ratings of 1 MW and higher. It contains information on solar arrays that went into service before mid-2024.

Follow the link and explore!

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Trade magazines and manufacturers make a specialty of holding training sessions, many at no cost.

Here is a source I am reading today on the website of Pumps and Systems magazine.

Two are upcoming, live webinars. Many more are On Demand recorded webinars.

Several are back-to-basics with an energy emphasis on control strategies (often no cost/low cost energy measures) or pump selection and piping design for optimizing energy utilization with the goal of improving plant productivity.

I need a few Professional Development Hours and I have picked out a couple for myself.

Here is the link.

https://www.pumpsandsystems.com/webinars

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Image: Grok

I wrote the following in a discussion on another website. The topic was a development in the stock market. I thought I would share my thoughts here. If it changes your thinking or changes your life please leave a comment.

+++++

I have a portion of my nest egg in stocks I pick. I have been watching for a long time. My first class in stocks and bonds was a short series of classes my junior high principal led. It was his effort to give us students some financial skills. That was 1968. It worked. I have used the basics I learned there ever since. I was so intrigued, one part of my college book-learning is in finance. His little class of the basics changed my life.

So, as a random presence on the internet, I will give you my advice on how to manage your retirement savings.

If you are independently wealthy and can do whatever you like and not run out of money, hire somebody to follow new developments that appear in the financial news. You may be a person who lives for risk and adventure. Go for it.

If you are what I call independently middle class, that is you can probably pay your own bills right through nursing home and your own funeral, diversify well as a hedge against disaster and if you pick any stocks yourself follow a value investor philosophy. Warren Buffett and Joel Greenblatt are authors in this category. Joel has a website where he screens for value stocks at no charge to you. Spend some of the profits on enjoying life and supporting causes dear to you. Prepay for your funeral, buy good lenses when you get cataracts, get good hearing aids, get a good lawyer to write your will and set up trusts that bypass probate, and pay the $99 per month for Full Self Driving in your car. Your old age will be more peaceful if you can do these things without fretting over the cost.

If you are still building your nest egg, spend time increasing your stack of skills and raising your income. Max out your company match in your 401k. Put money into mutual funds where someone else picks the stocks. Also, you may be in the years when you have children at home. If so, build some great memories with them. If not, build some great memories with whoever is in your life. The time will come when your world needs to shrink, quickly or slowly, but inevitably it will shrink.

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Do you know how to connect a generator to a house?

Craig Lawrence has shared his experience with providing a whole-house solution for outages using a portable generator. Here is a link to the first X post in his thread. Craig explains his plan and his commenters add their own stories.

Naming the exact pieces of equipment is not an endorsement by me or by Craig Lawrence. I present them as a real-world option with pricing available.

For project developers I will jump to the finances and put in a little extra for budgeting.

First cost

Generator $1100

50A cord $100

Electrical work $1200

LP tank $100

Total $2500

Operating cost

About one dollar per hour for propane fuel

Maintenance for the generator, probably similar to that for a gasoline lawnmower

Hardware

Here is the key to disconnecting your house from the utility power, and connecting to the generator. It is a manual lockout in the circuit breaker box and a generator inlet box. The idea is that you need to add a cord to your house so you can plug it into the generator’s outlets. The electrical power goes from the generator to the inlet box, and then into the circuit breaker box by backfeeding through its circuit breaker on the right side of the photo. Normally the utility power comes into the circuit breaker box through the main breaker shown at the top of the photo.

Never allow both sources, utility and generator, to be connected to your house at the same time.

Installing this equipment must be done by a licensed electrician. This is not a DIY project.

Then you need to have a cord that connects to the house and plugs in to the generator.

This is the one Craig is currently using. You can see the prongs on the end to the left in the picture. That end plugs in to the generator. The other end attaches to the generator inlet box.

Then you need a generator. Craig chose this one for use with LP gas.

Here is a close up of the outlet to use.

Here is more detail on the control panel. The outlet to use is the one labeled “120/240V AC 50A 14-50R.”

Here is a close up of the fuel tank connection. For this generator model the propane hose is included, but the tank is not.

The fuel tanks Craig mentions are commonly available in Texas for use with propane grills. Here is an example.

Read and follow the safety procedures for all pieces of equipment. Expect to use Personal Protective Equipment. Going beyond the manufacturer’s recommendation is prudent.

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https://spectrum.ieee.org/co2-battery-energy-storage

Here is an product that is at the point project developers look for. It solves a problem customers will pay to solve. The equipment is proven in use and available for purchase, but is early in the technology adoption cycle.

The lithium ion batteries in use today have a sweet spot of about 4 to 8 hours duration. The chemical process works well at that speed, and the economics work.

The plant in this photo produces 20 MW of power and has gas storage volume for 10 hours of use, so 200 MWh. Sunny Sardinia is a net exporter to the mainland and renewables are a significant fraction of the total generation capacity.

The IEEE Spectrum has an article with several links to supporting information. Here is what I have learned.

First, the business side.

• There is a manufacturer, Energy Dome.

• One unit has been built and is connected to the grid in Sardinia. More are in development by more than one customer in India and the US.

• Google is a partner and has plans to build several units.

• No new materials or equipment are required, what is new is the clever arrangement.

• Construction is faster than its competitors in energy storage.

• The manufacturer says the cost per unit of storage is less that its competitors.

• The contract structure can be a purchase of the equipment, or Energy Storage as a Service.

Next the physics and engineering in the thermodynamics and fluid flow.

• The storage medium is liquified carbon dioxide. The dome to the left contains carbon dioxide gas. The tanks to the right contain liquid carbon dioxide. The carbon dioxide is purchased from a supplier of industrial gases. This is not a carbon capture device.

• The carbon dioxide moves from gas to liquid during storage. It moves from liquid to gas during generation.

• The equipment in the middle is the compressors and condensers to liquify the gas during storage, and the evaporator and turbine which generate electricity.

• Carbon dioxide can be liquified using a high pressure with no mechanical cooling required.

• The process gives up heat during compression, and requires heat during expansion. The article mentions a thermal energy storage system.

Here is a quote from the article:

“Outside the dome, a series of machines connected by undulating pipes moves the CO₂ out of the dome for compressing and condensing. First, a compressor pressurizes the gas from 1 bar (100,000 pascals) to about 55 bar (5,500,000 pa). Next, a thermal-energy-storage system cools the CO₂ to an ambient temperature. Then a condenser reduces it into a liquid that is stored in a few dozen pressure vessels, each about the size of a school bus. The whole process takes about 10 hours, and at the end of it, the battery is considered charged.”

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