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New Power System Domination

New Power System Domination   New power systems dominated by variable renewables are set to become the new energy reality for nearly every country within the next three decades.   We forecast that by 2050, wind and solar will supply almost 70% of the world’s electricity. By then, global electricity consumption will have doubled compared to today. This significant increase in variable renewables will present many challenges and create new market dynamics for grids worldwide.   These are some of the key findings in our special report on New Power Systems, part of DNV’s Energy Transition Outlook series. Our report helps you understand the impact of this new power reality on national economies, energy security, and the pace of the energy transition. By 2050, we also find that:  
•          Global grid infrastructure is set to double to meet surging electricity demand
•          Electricity will be more than 90% decarbonized
•          Household energy expenditures will decline to 75% of 2021 levels in Europe and 50% in North America  

by the courtesy of DNV.

Is the Battery Energy Storage Solution an economical method for saving Energy, as of today available facility?

LFP is the economical BESS

LTO is the costly BESS

Air Cooling BESS is accepted

Liquid Cooling BESS accepted

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Energy Storage is the Base of Renewable Green Energy

#Green Future


(1)       Lithium Titanite Oxide – a wonder of the era with highly charge and discharge density with 30+ years life cycle. (2)  Lithium Phosphate, commercially viable and being used for Solar, Wind, EV, Backup and individual houses & multiple utilization.

Agenda is: To replace the fossil fuels by the renewable resources & energy. 

We are the project specialists from R&D to designing, supply of complete containerized energy storage solution to commissioning for your Energy storage requirements. EMS and full EPC for Mega projects by our Engineers.

We are one’s Renewable Energy partners from 30KWh to 200KWh and from 1MWh to 200MWh for industry, commercial entities, factories, Hospitals, farmhouses, Schools, collages, social gathering spots, Marriage halls, stations, Charging points, individual houses etc.

Our market strategy over the past years was to position the company for growth by selling products directly and through distribution channels. Major focus is / was targeting the projects in any size for energy storage solution. Management also focused on consolidating the business operations and identifying global Green Technology partners and integrators to prepare for expected growth in 2023. We strengthened our suppliers, trained our people, developed strategic partners, and built up our sales pipeline which typically requires a 3 – 4 months cycle. Our value proposition is closely aligned with biomass energy producers and we are also working to become more than just a value-added supplier of equipment.  We see real value in these types of applications as it creates more of a recurring revenue stream. Households, Commercial and industrial clients are our partner in spreading economical energy and reducing CO2 emissions with substantial cost-effective Energy Storage Solution. As a result, we are identifying large and scalable opportunities in this area, (UK, EU, Middle East and Africa) including licensing agreements and potential mergers and acquisitions.


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China Top 15 Power Battery Companies By The Installed…

On May 11th, the China Automotive Power Battery Industry Alliance released the monthly data for power batteries in April 2023. The data shows that in April this year, China’s power battery production totalled 47.0 GWh, a year-on-year increase of 38.7%; from January to April, China’s cumulative power battery production was 176.9GWh, a cumulative year-on-year increase of 28.7%. In terms of installed capacity, China’s power battery installed capacity in April was 25.1 GWh, a year-on-year increase of 89.4%; from January to April, China’s cumulative power battery installed capacity was 91.0 GWh, a cumulative year-on-year increase of 41.0%.

Regarding specific companies, in April 2023, CATL’s power battery installed capacity was 10.26 GWh, accounting for a high proportion of 40.83%, ranking first. Following closely behind was BYD, with a power battery installed capacity of 7.32 GWh in April, accounting for 29.11%.

At the same time, CALB, EVE, Gotion, Sunwoda, LG New Energy, SVolt, Farasis, and REPT also made it into the top ten list.

 From January to April this year, CATL’s power battery installed capacity was 39.51 GWh, accounting for a high proportion of 43.43%, ranking first. BYD’s power battery installed capacity this year was 27.73 GWh, accounting for a high proportion of 30.47% and ranking second.

 Additionally, in April this year, 36 power battery companies supported the installation of new energy vehicles in China, an increase of 2 compared to the same period last year. Overall, 42 power battery companies supported new energy vehicle installations in China from January to April this year, consistent with the same period last year. The top 10 power battery companies had a combined installed capacity of 89.1 GWh, accounting for 98.0% of the total installed capacity.  

By Kayla Li


Lithium Battery Industry

Why is the lithium battery industry so excited despite the rising price of lithium carbonate?

The recent phenomenon of upstream price increases being met with excitement in the downstream sector goes against traditional business intuition, but is a reality in the lithium-ion battery industry. This is due to the industry’s fervent desire for a fair and stable distribution of benefits between upstream and downstream players.

Starting on April 26th, the long downward trend in lithium carbonate prices finally showed signs of stabilizing. Resource companies that specialize in lithium carbonate products saw significant gains that day, with Wind’s lithium mining index rising over 3%. However, the performance of the downstream lithium-ion battery industry was even more impressive, with the Shenzhen Stock Exchange’s lithium-ion battery index surging over 5%. Industry insiders expressed their excitement on social media platforms.

The obvious reason why downstream companies, who are about to face higher purchasing costs due to the upstream price increase, are still thrilled is because the stabilization of lithium carbonate prices sends a positive signal. As a core raw material that cannot be avoided in the current lithium-ion industry, fluctuations in its price are propelled by speculative funds but also reflect changes in fundamentals and expectations.

Last year, lithium carbonate prices soared from CNY 27,500 per ton to CNY 60,000 per ton, accompanied by explosive growth of 93.4% in China’s new energy vehicle sales. However, in just four months since the beginning of this year, lithium carbonate prices have plummeted from CNY 50,000 per ton to CNY 18,000 per ton. This backdrop includes a 25.8% YoY slowdown in Q1 new energy vehicle sales and even negative YoY growth in January.

The receding tide has exposed the industry’s problem of temporary overcapacity and excess inventory. Industry statistics indicate that power battery inventory throughout the entire supply chain reached 164.8 GWh in 2022, which is enough to support four months of production based on estimated global power battery usage from last year. In the intermediate links such as lithium salt and positive/negative electrode materials, there are also high inventories lasting several months.

Recent quarterly reports reveal that lithium battery manufacturers such as Ningde Times are making significant efforts to reduce inventory. This is reflected in the downward trend of lithium prices, which have fallen below expectations and even below some companies’ production cost lines. Under the influence of high inventory and pessimistic expectations, downstream companies are not willing to purchase additional inventory even at tempting prices.

Now that there are signs of stabilization in lithium carbonate prices, cautious investors may not view this as a major demand reversal, but they should agree that the industry’s inventory reduction efforts have achieved certain results. Under favorable price conditions, downstream companies have begun to show an interest in replenishing their inventory.

The second reason may be more important: the long-awaited expectation of a “stable and reasonable price outlook” may be realized at the current price level. The large fluctuations in lithium carbonate prices in the past have disrupted industry trading order and threatened the healthy development of the industry. However, the current lithium carbonate price approaching CNY 20,000 per ton can be absorbed by downstream companies and is profitable for upstream companies, providing hope for achieving balance.

In the upstream sector, trading chaos such as lying flat, production cuts, and defaulting on orders were frequently seen during the period of the fastest decline in lithium prices. In early April, reporters found that the transaction volume of lithium carbonate had decreased by 30%-50%, with only long-term contracts maintained; some high-cost companies had significantly reduced production, and the monthly operating rate of China’s lithium carbonate in March was only about 55.62%. Every day, there were lower prices, leading to broken contracts for lithium carbonate purchases.

In the downstream sector, the sharp fluctuations in raw material prices have resulted in strong wait-and-see sentiment and the mentality of only buying when the prices rise, seriously disrupting the pace of downstream demand release. In the power battery market, the excessively low lithium carbonate price has kept consumers expecting a significant drop in new energy vehicle prices, leading them to choose to hold their money and watch. In the energy storage market, the bidding progress for large-scale energy storage orders slowed significantly in Q1.

What is more worrisome is that the large fluctuations in prices have distorted the necessary investment actions of enterprises in the lithium-ion industry. The most typical incident was the abandonment of the exploration of Wushanxia Nan lithium mine despite a premium price increase nearly 400 times and a transaction value of CNY 6 billion. The excessive price increase led to impulsive premiums, which were followed by an excessive price decline that brought the promised investment to a sudden stop.

In short, the sharp rise and fall of raw material prices are not in the interest of any player in the entire industry chain. Nowadays, as automobile sales are about to enter the traditional peak season and energy storage demand has accumulated for some time, it is crucial to establish a stable and reasonable lithium carbonate price in order to achieve normal.

By the courtesy of Kayla Liu

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Future of Lithium Phospate

Battery Raw Materials – 10 year forecast
Will scarce raw materials grind the lithium battery market to a halt?
Research and Written by : Roz Hilton

Can the mining industry can keep up with demand
for raw battery materials?
The qualified answer is yes. But not without some shortages and some price hikes.
There are tons of detractors taking to social media platforms suggesting that raw materials mining just simply cannot keep up with demand and that this fact alone will see the EV market fall flat on its face. So we thought we’d do some modelling and the outcome is our forecast on battery raw materials entitled “Will scarce raw materials grind the lithium battery market to a halt?”  This report takes a long hard look at whether or not battery raw materials will run out, as the battery industry ramps up output. In 2023 we will see 621 GWh of batteries produced for EVs sold in the three largest territories – China, Europe’s 5 largest economies and the US.
  Lithium and Graphite supply will be under strain through to 2026.
  The Inflation Reduction Act’s insistence on new supply lines will see most market opt for LFP, LMFP or M3P batteries, because of the ease of setting up supply chain.
  Manganese demand will increase significantly with the advent and following acceleration of LMFP production.
  Demand for nickel (NMC) and cobalt-based chemistries will fall and be limited to North America at the top end of car markets.
  Graphite is the next big problem for battery makers due to its current heavy concentration within China.
CONTAINER TYPE ENERGY-LFP-1000kW-1MWh-E-04 Uncategorised

Hike in Lithium Prices

Much of the current movement to decarbonize the grid involves installing many gigawatts of battery-based energy storage. Lithium-ion technology is leading the way with breathtaking advances that are addressing everything from improved performance to strategies to mitigate the risk of fires. But the rapid development is causing numerous challenges.

The high demand for lithium-ion batteries has translated into shortages of lithium along with shortages of other essential commodities like copper, aluminum, nickel and cobalt. As we all learned in Market Economics 101, limited supply caused by high demand leads to high prices, market volatility and long lead times.

In the span of a year, between March 2021 and March 2022, lithium carbonate prices jumped from around $12,000 per ton to $78,000 per ton. Pricing for other commodities rose too, though not as dramatically. While lithium stabilized somewhat during 2022, pricing began advancing again by the end of the year.

Large-scale battery energy storage systems (BESS) projects are taking the brunt of these factors, with lead times stretching up to a year for large capacity orders — and pricing uncertainty that has led to a transfer of pricing risk via indexed pricing strategies that manufacturers began using in early 2022.

By the courtesy of : By JASON BARMANN | Republished with permission from Burns & McDonnell

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Renewable Energy merits and drawbacks in application for Masses

By Khubaib Khan – Director ECO ESS Ltd. UK

Dark clouds and faded greenery are asserting openly and challenging to the humankind if you don’t awaken then get ready for more strikes – bad to worse breathing atmosphere has become the anti-body free of cost silent killer for many and despite of a buzz we don’t wake up.

Shielding of the atmosphere & our surroundings is the responsibility of the individuals but not only for the authorities. Let’s contribute by changing this unpredictable environment into a friendly nature. Handful Cos. in the UK, EU and USA have been contributing towards clean energy and swapping fossil fuels energy by renewable energy and sustainable energy that’s ultimately directing towards Zero CO2 emission. We all must be ambitious in this expedition and say let’s promote renewable energy and store valuable energy for better tomorrow, for the world & for the generation to come. In Unies, colleges and schools, we must add a line in title of their text books and notes – “Save the earth and save the nature by going green”.

With my immense research work, I identified that strong loophole persists in implementation and awareness of renewable energy on the mass level, despite of the loud slogans, activates, COP26 agenda, meetings, exhibition, seminars incentive schemes, big talks in developed countries specially in the EU, UK and in the USA. Ironically, Asia & Africa are unaddressed except China where the pollution and CO2 are its max. level of this era.

Green West does not nuisance for the polluted Asian & African atmosphere. Policies have been drafted, PM of few countries and their legislatives are in scene but reality is, their own progress is slow indeed and least public awareness being generated. Mega projects for renewable energies are in hands of few. The supplier i.e. manufacturer and buyer’s bond is stiff enough that the small Pvt. sector cannot courage to jump into this sector. Funds are for those Cos. who are the giant and can build-up mega project but what about small enterprises and individuals – how to encourage them? Is a valid question.

The major types of renewable energy sources are:

In this instance, I started asking my peers and industries fellows including capitalist and Tycoons of Gigawatt-projects owners what is the solution of slow coach towards decarbonisation? Why the hydraulic and Biomass / Waste energy cannot be the replacement?

Answer is unanimous, ‘most of the nation cannot afford hydraulic energy since don’t have much infrastructure and water flows and waste energy is another CO2 source somehow’. Compressed natural Gas is disputed – either its free from CO2, better than fuel or its lesser harmful than others fossil fuels. Thermal energy is also in doubt too either it is the best source for energy production or harmful to humankind? Blue energy is practically in fantasies and theories and in hand of few generalists and with money makers & markets. No one has seen blue energy so far, their actual form and how it can be generated. In fact, blue energy is just a theory and not coming to the practical review anywhere except in few texts. 

Therefore, Long duration Energy Storage Solution (ESS) is needed to substantiate the Renewable Energy for masses either extracted by Wind or by Solar energy. One of the best option and solution is Lithium Titanate Battery for individual houses from 3KW/h to 10KW/h. Though, LTO is relatively costly but pays off its cost in few years since life cycle is 30+ years. LTO is the safest, fastest and highly efficient ESS in both charging and discharging states. But LFP realistically is the economical solution as of today. It is the best option for individual houses, small industries, farm houses, machineries, backups etc even for EV and Electric cars can rely on this Li Ion form. This is another topic as a whole that prices are being rocketed and one could say this is due to the demand vs. supply. But questions are raised on Li Ion batteries as well – Millions of boxes where to be dumped after their usage and expiry or it’s another add on to the pollution and destroying the nature. Answer was received – these are minerals or synthetically produced molecules and can be dumped to the nature earth from where they originated – answer is elementary and needed further debate since Govt of UK have published 100s of pages on Li Lion batteries where and how to dump safely after their expiry – these good deeds with good intention by UK Gov. raised 10s of questions spontaneously.   

In my strong opinion, Westerns Govts must ponder on the LFP factor till the time energy distribution should emerge from the alternative mega solar plants along with wind parks. Automobility has to run on the aid of these Li Ion batteries since they don’t have other option so far in this era unless something originated from the surface to replace these powerful and long-lasting Li Ion batteries. 

I had extracted few excellent articles and quotes which are self-explanatory and would clarify the picture which is gloomy but foggy as far as commercial part is concerned and needed a lot of attention from top world-wide think tanks – if not today then get ready to face rebellious nature tomorrow in form of more shocks, jolts, floods, tsunami, drought, hunger, poverty and faded nature. (God forbid)  

Energy Storage Latest

“Renewable energy has come a long way in the past decade, and it’s still trending upward going into 2022. These days, “carbon-efficient, all-natural” energy is the norm, incorporated into everyday life with an irreversible effect on society.

The International Renewable Energy Agency (IRENA) names renewable energy the backbone of global development and climate strategy.

In other words, our world has become dependent on renewable energy. Production has increased exponentially and the world has doubled its capacity over the past decade. But the main contributor to renewable energy’s success is the way in which we store that energy. It has an enormous shelf life, which increases demand.

In fact, this growth will increase by 13 times in grid-scale storage by 2024.

This is a monetary equivalent of $71 billion.

Global Market Insights sees energy storage systems reaching $500 billion by 2025.

Energy storage including lithium batteries, solar panels, and microinverter-based storage systems allows this renewable energy boom to continue.

Not to mention energy storage also allows for a massive opportunity to enter the market in a very solid and secure way.

And I happen to have three red-hot energy storage stocks that can get you started in profiting from the renewable energy industry.”

Sorce: by wealth daily

Energy Stoarge is the Future

“The energy storage industry should play a proactive role in supporting market development in Southeast Asia, a panel discussion at the Solar and Storage Finance Asia event heard this week, from Aquila Capital regional CEO Alexander Lenz. We speak exclusively with Yaron Ben Nun, CTO and founder of Nostromo, a start-up aiming to commercialise a new ice-based energy storage for cooling buildings and Yaron is adamant that it can turn electricity demand for commercial buildings into a powerful tool of the energy transition. US independent power producer Talen Energy has hired developer Key Capture Energy to work on a battery project at one of its coal power plant sites in Maryland, as Talen pursues its new ESG-driven path. Koch Industries, another name more commonly associated with fossil fuels, has invested in zinc-based energy storage company Eos, through its Koch Strategic Platforms investment vehicle. The UK’s Flexion Energy has gained a US$200m+ investment commitment from an infrastructure investment group as it targets development of a 1GW battery storage portfolio and in South Australia, developers Maoneng and SAPGen are seeking permission to construct 465MW of large-scale battery storage, solar-plus-storage projects behind-the-meter and in front-of-the-meter make progress in Hawaii. Finally, we round up some news about investors acquiring three US solar and storage developers, which could be a sign of things to come.” By Andy Colthorpe


“The global transition to renewable energy has been accelerating worldwide, driven by the urgent imperative to address the climate emergency and increasingly favourable economics.

This has been supercharged by the impact of the Covid-19 pandemic, creating unique conditions to accelerate the transition, with the IEA recognising that renewable energy, such as wind and solar, showed ‘a degree of immunity to the crisis’.1 The temporary acceleration of the share of renewable energy driven by Covid-19 has fixed the eyes of the world’s energy leaders on the opportunity to realise the potential of renewables to reduce emissions, permanently. The UK is one such test-case.

The UK Prime Minister has increased the Government’s offshore wind target from 30 GW to 40 GW by 2030 and pledged that offshore wind will power every home in the country in that time. This will form a keystone in the country’s path to a net zero energy system.

The UK Government will soon release its energy white paper, detailing its strategy for the coming decade and beyond. This is an opportunity to set an ambitious target for renewable energy to become the primary source of power by 2030. In 2019, the UK energy system reached 37% renewable energy.

By 2030, modelling undertaken by Wärtsilä shows that the country could easily achieve a permanent 62% renewable generation, even with the energy system as it is today. The country should go further, setting a target to achieve 80% renewable energy by the end of the decade. That may sound ambitious, but it is realistic. During the initial Covid-19 lockdown, when energy demand fell by up to 10%, the energy system as it is today coped with up to 60% renewables for short periods. Energy systems in other European countries, such as Germany and Spain, achieved over 70% renewable energy. If current systems can manage major spikes of renewable energy today, then – as this report shows – with investment in technologies that add system flexibility, we can be confident to set ambitious targets for permanently higher levels of renewables in the near future.”

Source: Wärtsilä Energy Transition Lab Report by Ville Rimali Growth & Development Director

The question of bankability: From tech to revenue model

Laurent Segalen states that “from a financial point of view, li-ion batteries are now a fully bankable technology. World-class providers like Fluence and Tesla are delivering new products with up to 20,000 cycles and above 90% round-trip efficiencies. And lithium ferro phosphate (LFP), with its lower cost and reduced fire risk, seems now the chemistry of choice for stationary storage.

Now that the technology aspect has been sorted, how can the revenue model of stationary storage become bankable? Contrary to wind and solar, batteries don’t typically benefit from long-term secured revenues, such as power purchase agreements (PPAs).

Instead, investors in storage need to deal with several types of revenues (arbitrage, grid services, reserve) which are difficult to model. Even more important, capturing those new revenues relies on implementing ever-improving software that maximise the monetisation of the numerous market opportunities but can be often seen as “black boxes” by investors.

The software race is on. Against Tesla’s Autobidder, you see Fluence acquiring AMS to provide an integrated hardware + software solution. That new software is incomparably more suited to optimise battery assets than human traders. For instance, in Australia, the new market design has created five-minute bidding windows: the best human trader will post 15-20 trades a day, whereas the software will be able to bid 288 times (12 bids per hour x 24h).” Published in Financier, renewable energy transactions.

Summary:  I could sum up in below sentences.

The renewable energy problem:

There are some days when;

  • the sun doesn’t always shine, and
  • the wind doesn’t always blow.
  • And then there are days when these happen for extensive periods.
  • This causes intermittency & variability of your renewable energy generation.

The natural environment has a massive impact on the balancing capability of renewables. Which often results in decreased commercial capability of your renewable assets.

How can we increase the capability of renewable assets?

Grid scale storage solutions

By applying unique storage expertise into renewable energy generation projects, one can transform the value of your assets, ‘get a detailed roadmap for your route to the market and achieve your goals.’

Why Do You Need a Solar Battery Storage System?

Pairing solar batteries with solar arrays is a relatively new practice, but an effective one. You can benefit from solar battery storage in 4 key ways:

  1. Store energy for later use
  2. Significantly lower your energy costs
  3. Earn money by selling stored energy to the grid
  4. Become independent from the grid 

Firstly, a solar battery stores the energy generated during sunlight hours and makes it readily available for use during non-production hours, such as at night or on cloudy days, essentially enabling your home to run on 100% renewable solar energy around the clock, as long as electricity demand does not exceed the supply that the battery can provide.

In addition, solar battery backup power can lower your energy costs significantly. By charging the solar battery during off-peak hours and discharging it during peak hours, you can avoid paying a lot for electricity from your utility company. The savings from this can serve towards reducing your battery system costs.

What’s more, you can earn money by selling the energy stored in your solar battery back to the electrical grid when electricity prices are at their highest—if your utility allows net metering.

Finally, by adding a solar panel battery to your solar system, you can choose to be independent from the national grid at any time, thereby ensuring energy security for your household. Naturally, the how many solar panels you need to install for this will vary depending on your energy demands and budget.

Source: Green Match

saleable Energy Storage Solution

AC vs. DC Coupling Energy Storage Systems

Lucas Miller March 4, 2021

At Mayfield Renewables, we routinely design and consult on complex solar-plus-storage projects. In this article, we outline the relative advantages and disadvantages of two common solar-plus-storage system architectures: AC coupled and DC coupled energy storage systems (ESS).

Before jumping into each solar-plus-storage system, let’s first define what exactly a typical grid-tied interactive PV system and an “energy storage system” are.

Looking at the diagram below, a simplified interactive PV system is composed of a DC power source (PV modules), a power converter to convert from DC to AC (interactive inverter), and AC loads (main service panel). 

When the sun is shining, the PV modules produce DC power. That power is fed through the interactive inverter which then feeds the main service panel. The interactive inverter “interacts” with the grid to send excess power to the utility and also will shut down during a power outage. This prevents the PV modules from producing power which could energize downed power lines.

Interactive PV System String Inverter.MR logo.png

Now that we have a simple grid-tied system, let’s build onto it by adding energy storage. The 2017 Article 706.2 of the National Electrical Code (NEC) defines an energy storage system as: “One or more components assembled together capable of storing energy for use at a future time. ESS(s) can include but is not limited to batteries, capacitors, and kinetic energy devices (e.g., flywheels and compressed air). These systems can have ac or dc output for utilization and can include inverters and converters to change stored energy into electrical energy.”

For the purposes of our analysis, we loosely define ESS as a component(s) of our circuit designed to store energy for later use (e.g., a lead-acid or lithium-ion battery bank).

AC Coupled Systems

As mentioned above, PV modules will produce DC power. That power must be converted to AC to be used in most commercial and residential applications (e.g., typical electrical loads for buildings and homes). In contrast, battery cells must be charged with DC and will output DC power. The AC-DC distinction has major system design implications.

In an AC coupled system, power from the PV modules is converted to AC prior to connecting to the ESS. In other words, the output from the PV modules is fed through an interactive inverter before it reaches the ESS. This means that the power must be converted to DC before charging the ESS, and any power output from the ESS must be converted once again to AC. To achieve this, an additional multimode inverter is required.

AC Coupled Multimode System.MR logo.png

Moving from left to right in the diagram above: The PV array produces DC power, which is immediately converted to AC by the interactive inverter. That power feeds a backup loads panel containing select loads formerly located in the main service panel. The backup panel is also connected to the ESS, with a multimode inverter acting as a middleman to convert AC to DC when the ESS is charging, and DC to AC when discharging.

In this setup, it’s possible for the PV array, backup loads panel, and ESS to operate independently from the grid. During a power outage, the multimode inverter—using power from the ESS—will mimic signals from the grid, allowing the interactive inverter to stay online and the PV array to continue producing power to feed the backup loads panel and charge the ESS with any excess power.

DC Coupled Systems

DC coupled systems rely only on a single multimode inverter that is fed by both the PV array and ESS. With this system architecture, DC output power from the PV modules can directly charge the ESS. No DC-to-AC conversion is required between the PV array and ESS. 

The backup loads panel and main service panel—both of which require AC power—are placed downstream from the multimode inverter. In the case of a power outage, the microgrid interconnect device (which is commonly integrated into the multimode inverter) will cut off the multimode inverter’s output to the main service panel but the inverter will continue to supply AC power to the backup loads panel.

DC Coupled Multimode System.MR logo.png

Moving from left to right in the diagram above: The PV array outputs DC power to the ESS and the multimode inverter. The multimode inverter will convert the DC power to AC and any power in excess of the loads in the backup and main service panels (or that is used to charge the ESS) is exported to the grid.

Advantages of AC Coupling


Adding an ESS to an existing grid-tied interactive PV system is not uncommon. Doing so can cause headaches for system designers, and the easiest solution is often AC coupling the new ESS. 

Compare the simple interactive PV system and the AC coupled system above. Note that in both cases, the PV side of the system is the same. AC coupling will add a backup loads panel and multimode inverter but, crucially, the existing PV system does not need to be redesigned. 

Higher Inverter Capacity

A DC coupled system relies on only a single multimode inverter and is thus limited by its capacity. AC coupled systems have two inverters (one interactive and one multimode), both of which feed the backup loads panel. So if an outage occurs while the sun is still shining, the backup loads panel can have the kW capacity of both inverters available.  


As with any electrical system, PV designers should consider potential points of failure. In an AC coupled system, if the battery-based multimode inverter is disabled, a simple bypass switch will keep the PV array and interactive inverter online (as long as the grid is up). This is not the case for DC coupled systems, which are reliant on a single multimode inverter at the heart of the system architecture. 


Interactive inverters tend to be more efficient than multimode inverters. If the sun is shining and the power being produced is consumed immediately (i.e., the power output from the PV array is directly feeding the loads rather than passing through the multimode inverter to charge the ESS) an AC coupled system architecture will be more efficient than its DC counterpart. 

Advantages of DC Coupling


While an AC coupled system is more efficient when the PV array is feeding loads directly, a DC coupled system is more efficient when power is routed through the ESS (e.g., when the ESS is charged directly and discharged at a later time) since there is only one conversion from DC to AC—a single inverter, rather than two, to pass through.

Full PV Array Power

In typical interactive and AC coupled systems, inverters are downsized under the assumption that the PV array will rarely, if ever, produce at its nominal rating. For example, consider a 5kW PV array that is tied to a 4kW interactive inverter. This hypothetical system is now limited to a nominal 4kW power output. 

For DC coupled systems, the power feeding the ESS is not limited by an interactive inverter. Returning to the hypothetical system above, but without the interactive inverter this time, a theoretical maximum of about 5kW could be used to charge the ESS and/or feed the multimode inverter without any power limiting. 

Direct Charging

Low-battery-voltage situations can arise within AC coupled systems. If too much energy is pulled out of the battery bank during an outage, that energy can cascade throughout the system, shutting down the multimode inverter, then the interactive inverter and the PV array. Since there is no way for the PV array to directly charge the batteries in this case, system owners may have to wait for grid power to return before the system can come back online.

Conversely, a DC coupled system can continuously send power (during daylight hours) directly from the PV array to the ESS. The unincumbered pathway between the PV array and battery bank allows the battery voltage to rise and thus the multimode inverter can turn back on and supply power to the backed-up loads without having to wait for the grid power to return.

Source : Mayfield

Battery Pack Co2 Emission

What are the driving forces behind decarbonisation?

“COP26 aside, financiers are being driven to invest in decarbonisation by the brute reality of the climate crisis, by public pressure, and by shifting market forces.

Spooked by the risks of inaction, 45% of banks disclosing to CDP — the global environmental impact disclosure non-profit group — have aligned their portfolios with net zero. This empowers green technology companies. 

Despite the pandemic, 260GW of new renewable generation was deployed globally in 2020 – smashing former records by almost 50 per cent. The electric vehicle (EV) sector raised US$28 billion, 10 times more than in previous years.

And we are seeing increasing support for the key technology linking renewable generation with zero-carbon transport: battery storage. 

The forces behind the energy transition are expanding the market for new storage technologies. The global storage market is poised to increase by 23% by 2030. As the market grows, regulation will respond, making it easier for battery operators to meet the needs of energy systems. 

We are already seeing this in the UK. The Government is consulting on opening up the transmission network to competition, so that new technologies can resolve constraints at lower costs to consumers. The Pathfinders programme of the national electricity system operator National Grid ESO, is enabling operators to stack revenues, so that they can provide multiple flexibility services at once.

These changes make it more likely that we will hit the 18GW of storage capacity we need to run a zero-carbon system.”

By James Basden

Eco Ess Banner Energy Storage Solution

The question of bankability: From tech to revenue model

“From a financial point of view, li-ion batteries are now a fully bankable technology. World-class providers like Fluence and Tesla are delivering new products with up to 20,000 cycles and above 90% round-trip efficiencies. And lithium ferro phosphate (LFP), with its lower cost and reduced fire risk, seems now the chemistry of choice for stationary storage.

Now that the technology aspect has been sorted, how can the revenue model of stationary storage become bankable? Contrary to wind and solar, batteries don’t typically benefit from long-term secured revenues, such as power purchase agreements (PPAs).

Instead, investors in storage need to deal with several types of revenues (arbitrage, grid services, reserve) which are difficult to model. Even more important, capturing those new revenues relies on implementing ever-improving software that maximise the monetisation of the numerous market opportunities but can be often seen as “black boxes” by investors.

The software race is on. Against Tesla’s Autobidder, you see Fluence acquiring AMS to provide an integrated hardware + software solution. Those new software are incomparably more suited to optimise battery assets than human traders. For instance in Australia, the new market design has created five-minute bidding windows: the best human trader will post 15-20 trades a day, whereas the software will be able to bid 288 times (12 bids per hour x 24h).”

Laurent Segalen

Financier, renewable energy transactions