We’re proud to share the completion of a new 400kW rooftop PV project in Xiang’an, Xiamen. From contract signing at the end of April to grid connection on May 29, this project set a new internal record for JinMega—just 21 days from initial site entry to final commissioning. 

Designed with our ballast-based mounting system using concrete blocks, the installation delivers both structural stability and efficiency, perfectly suited for flat industrial rooftops where penetration is not permitted. The solution ensures ease of installation, minimized roof load, and long-term durability, even under coastal climate conditions. 

Looking for more high-performance rooftop solar solutions? Explore our latest systems here

One.Increase the self-consumption rate of renewable energy
1. Solve the problem of curtailment of wind and solar powerIn the process of renewable energy development, the curtailment of wind and solar power is relatively serious. Wind and solar power generation are limited by natural conditions and are characterized by intermittent and fluctuating characteristics. For example, the magnitude of the wind is unstable, and the light is strong during the day and no light at night. When the power system is unable to absorb renewable energy in time, curtailment of wind and solar power will occur. Through wind and solar hydrogen production, the excess wind power and photovoltaic power are used for hydrogen production by electrolysis of water, which can be converted into hydrogen as a high-value energy carrier. This not only increases the self-consumption rate of renewable energy, but also reduces the curtailment rate of wind and solar power, and improves the economic benefits of the entire renewable energy power generation system.
2. Stable power output: Wind and solar hydrogen production system can stabilize the power output of renewable energy to a certain extent. When the power of renewable energy generation fluctuates, the power of hydrogen production from water electrolysis can also be adjusted accordingly. For example, when the power of wind power increases instantaneously, the power of the electrolyzer is increased, and the excess wind power is used for hydrogen production, thereby smoothing the power output and facilitating the better integration of renewable energy into the grid.
Two. Environmental benefits
1. Zero carbon emissionsCompared with traditional fossil fuel hydrogen production (such as coal to hydrogen and natural gas to hydrogen), the wind and solar hydrogen production process does not produce greenhouse gas emissions such as carbon dioxide. In the process of electrolysis of water, the only by-product is oxygen, and the entire hydrogen production process achieves zero carbon emissions. If the hydrogen obtained from wind and solar hydrogen production is used in fuel cell vehicles, industrial heating and other fields, it will greatly reduce carbon emissions in these fields, which is of great significance to the response to global climate change.
2. Reduce air pollutionThe traditional fossil fuel hydrogen production process will produce a large number of pollutants, such as sulfur dioxide, nitrogen oxides, particulate matter, etc. These pollutants can cause serious harm to air quality and human health. The absence of these pollutants in the process of hydrogen production from wind and solar helps to improve local air quality and reduce environmental problems such as haze.

Three. Energy security and diversification
1. Reduce dependence on fossil fuelsAs the global demand for fossil fuels continues to grow, the reserves of fossil fuels such as oil and natural gas are gradually decreasing, and energy supply is facing huge challenges. Wind and solar hydrogen production offers a new avenue for energy supply, reducing dependence on fossil fuels. Through the large-scale development of wind and solar hydrogen production, energy self-sufficiency can be achieved to a certain extent, especially in areas with abundant renewable energy generation, which can improve the security of local energy supply.
2. The diversified development of energy and hydrogen production from wind and solar energy has enriched the types and supply methods of energy. As a clean energy source, hydrogen can be applied in many fields, such as transportation, industry, energy storage, etc. The combination of wind and solar resources and hydrogen production technology has enabled the energy system to develop from the traditional fossil fuel to a diversified and clean direction, and improved the flexibility and adaptability of the energy system.
Fourth, the potential of industrial applications
1. Application of hydrogen in the chemical industry In the chemical industry, hydrogen is an important raw material, which can be used for the production of chemical products such as synthetic ammonia and methanol. At present, the production of these chemical products mostly relies on fossil fuels to produce hydrogen, and the use of wind and solar hydrogen production can provide a green and sustainable source of hydrogen. This will not only help the chemical industry to save energy and reduce emissions, but also improve the green competitiveness of chemical products. For example, methanol synthesized from green hydrogen can be used as a clean fuel or chemical raw material in more green industrial chains.
2. Application of hydrogen in the steel industry In the steel industry, hydrogen can be used as a reducing agent to replace the traditional coal reducing agent for the reduction reaction of iron ore. This process, known as hydrogen metallurgy, is an important way for the steel industry to achieve a low-carbon transition. Wind and solar hydrogen production provides a large source of green hydrogen for the steel industry, which can help the steel industry reduce carbon dioxide emissions, improve energy efficiency, and achieve sustainable development.

I. Industrial Sector

（1）Chemical Synthesis: In chemical production, it is used to synthesize important chemical raw materials such as ammonia and methanol, providing hydrogen sources for related industries.

（2）Metal Processing: During the smelting and processing of metals, it is utilized in processes like metal reduction and heat treatment to enhance the quality and performance of metals.

II. Energy Sector

（1）Grid Energy Storage: Excess electrical energy from the power grid can be converted into hydrogen for storage. During peak electricity demand periods, the stored hydrogen can be converted back into electricity through means such as fuel cells, achieving peak shaving and valley filling of the power grid and improving its operational stability and flexibility.

（2）Distributed Energy Systems: Combined with renewable energy generation devices like solar and wind power, it helps construct distributed energy systems, addressing the intermittency and instability issues of renewable energy generation and ensuring a stable energy supply.

III. Transportation Sector

（1）Hydrogen Fuel Cell Vehicles: It provides high-purity hydrogen for hydrogen fuel cell vehicles as their power source. These vehicles offer advantages such as zero emissions and long driving ranges, contributing to the reduction of carbon emissions in the transportation sector.

IV. Other Sectors

（1）Hydrogen-based Metallurgy: In the steel industry, it is used for the direct reduction of iron ore, replacing the traditional coke-based ironmaking process and reducing carbon dioxide emissions.

（2）Electronics Industry: It provides high-purity hydrogen for processes like reduction and cleaning in semiconductor manufacturing and electronic component production within the electronics industry.

Hydrogen is a very active reducing agent (fuel). Thus, in hydrogen-oxygen fuel cells, very high operating currents and high specific power values per unit weight can be achieved. However, the handling, storage, and transportation of hydrogen fuel is complex. This is primarily a problem for relatively small portable power plants. For such a plant, liquid fuels are more realistic.
Methanol is a very promising fuel for small portable fuel cells. It is more convenient and less dangerous than gaseous hydrogen. Compared to petroleum products and other organic fuels, methanol has a fairly high electrochemical oxidation activity (although not as high as hydrogen). Its chemical energy ratio content is about 6 kWh/kg, which is lower than that of gasoline (10 kWh/kg), but quite satisfactory. For this reason, its application in fuel cells for power plants in electric vehicles and different portable devices is widely discussed today.

The operation of DMFCs has fundamental problems that do not exist in proton exchange membrane fuel cells. In the latter, the membrane is practically impermeable to reactants (hydrogen and oxygen), preventing them from mixing. In contrast, in DMFC, the membrane is partially permeable by methanol dissolved in an aqueous solution. For this reason, some methanol penetrates from the anode part of the battery through the membrane to the cathode part. This phenomenon is called cross-curium-crustic ethanol. This methanol is directly oxidized by gaseous oxygen on a platinum catalyst without producing useful electrons. This has two consequences: (i) a significant portion of the methanol is lost in the electrochemical reaction, and (ii) the potential of the oxygen electrode shifts to a lower positive value, so the operating voltage of the fuel cell decreases. Despite many investigations conducted so far, it has not been possible to fully address this issue.
One potential application area for DMFC is low-power (up to 20W) power supplies for electronic devices such as laptops, camcorders, DVD players, mobile phones, medical devices, and more. At present, the application of DMFC as a power source for electric vehicles is very far away. Despite a great deal of research, DMFCs are still not in commercial production or widely used in practical use compared to proton exchange membrane fuel cells.

In the selection of hydrogen production technology, the choice between proton exchange membrane (PEM) electrolyzer and alkaline electrolyzer requires a comprehensive consideration of many factors. The following comparison will help you make a decision:

I. Technical performance

1. Current density and energy consumption

• Alkaline electrolyzer: The current density is usually 0.2–0.4 A/cm², and the system energy consumption of the two is similar.

• PEM electrolyzer: The current density reaches 1–2 A/cm², and the system energy consumption of the two is similar.

2. Load range and response speed

• Alkaline electrolyzer: Load adjustment range 40-100%, slow start and stop speed (hot start 1–5 minutes, cold start 1–5 hours), not suitable for intermittent energy such as wind power/photovoltaic power - pressure balance is required to avoid gas leakage.

• PEM electrolyzer: Load range 0%–120%, fast start and stop (hot start <5 seconds, cold start 5–10 minutes), very suitable for matching fluctuating renewable energy.

2. Cost factors

1. Equipment cost

• Alkaline electrolyzer: low cost, electrodes do not contain precious metals. The domestic market share is high, and the equipment price is only 1/4–1/6 of PEM.

• PEM electrolyzer: high cost (overseas price is 1.2–1.5 times that of alkaline, and 4–6 times that of domestic), because the catalyst requires precious metals such as iridium and platinum. However, overseas price performance is better, and domestic production is reducing costs through localization and scale.

2. Operating cost

• Alkaline electrolyzer: low equipment cost, high energy consumption, and energy consumption optimization in the future.

• PEM electrolyzer: low energy consumption can reduce costs, but equipment and precious metal expenses push up overall operating costs, and cost reduction depends on increasing current density, reducing iridium usage and localization.

3. Application scenarios

1. Alkaline electrolyzer applicable scenarios:

• Large-scale industrial hydrogen.

• Scenarios with low water quality requirements: ordinary deionized water can be used, suitable for areas with limited high-purity water supply.

2. PEM electrolyzer applicable scenarios:

• Renewable energy coupling scenario (wind power/photovoltaic): fast response, wide load range, suitable for off-grid distributed hydrogen production (such as islands, mining areas).

• High-purity hydrogen scenario (such as hydrogen refueling station): directly produce high-purity hydrogen without additional separation.

IV. Future trends

• Alkaline electrolyzer: focus on reducing energy consumption (upgrading diaphragms/catalysts) and improving current density to further optimize cost performance.

• PEM electrolyzer: through technological breakthroughs (reducing the use of precious metals), localization and scale-up cost reduction, it is expected that the market share will expand after the cost reduction.

Summary

• Choose alkaline electrolyzer: if the demand is large-scale low-cost hydrogen production, and the purity of the water source needs to be taken into account.

• Choose PEM electrolyzer: if you focus on fast response, adapt to the fluctuations of renewable energy, pursue high-purity hydrogen, and can accept a higher initial investment.

Green hydrogen is hydrogen obtained by splitting water from renewable energy sources such as solar and wind energy, and when it is burned, it produces only water, achieving zero carbon dioxide emissions from the source, so it has earned the excellent title of "zero-carbon hydrogen".
Although hydrogen energy is a clean and sustainable new energy source that does not emit carbon dioxide in the process of releasing energy, the current process of producing hydrogen energy is not 100% "zero-carbon". For example, the production of gray hydrogen and blue hydrogen, the other two brothers of green hydrogen, is divided into three categories: gray hydrogen, blue hydrogen, and green hydrogen, according to the source of production and the emissions in the production process.
Grey hydrogen is produced by the combustion of fossil fuels such as oil, natural gas, coal, etc., and although the manufacturing process is low-cost, gray hydrogen is the least popular among the "three brothers" due to the large amount of carbon dioxide emitted from the whole process.
Blue hydrogen is an "upgraded" version of grey hydrogen, made from fossil fuels such as coal or natural gas. While natural gas is also a fossil fuel and produces greenhouse gases when producing blue hydrogen, advanced technologies such as carbon capture, storage and utilization can capture greenhouse gases and ultimately enable low-emission production with reduced environmental impact. Grey hydrogen is used as a fuel for transportation, which actually emits more than direct diesel and gasoline. Compared with grey hydrogen obtained from industrial raw materials, green hydrogen is more pure and has fewer impurities, making it more suitable for fuel cell vehicles and promoting the clean transformation of the transportation sector.
In the chemical industry, hydrogen is often used as a feedstock for the production of ammonia methanol and other chemicals. The emergence of green hydrogen not only contributes to the deep decarbonization of the ammonia production process, but also replaces natural gas and coal for the production of green methanol, reducing carbon emissions in the production of chemicals.
In addition, asphalt can also solve the problem of excess renewable energy generation, and reuse curtailment of wind, solar and water, thereby increasing the utilization rate of renewable energy.
In 2022, the proton exchange membrane water electrolysis hydrogen production system of the Dachen Island Hydrogen Energy Comprehensive Utilization Demonstration Project in Zhejiang Province successfully achieved hydrogen production. Tourism and aquaculture are the island's two pillar industries, and the "green hydrogen ™ integrated energy system can supply electricity and heat for homestays, hotels, villas, etc." The oxygen produced in the hydrogen production process can be provided to yellow croaker farmers, giving full play to the value of hydrogen production by-products and providing impetus for the development of the local aquaculture industry. Green hydrogen is so good, isn't its appearance fee very "expensive"? The amount of electricity required to produce hydrogen by electrolysis is huge, and it takes about 50 kilowatt-hours of electricity to produce one kilogram of hydrogen, which is prohibitively expensive. However, with the further maturity of wind power, tidal power, solar power generation and other technologies, the production cost of green electricity has been reduced, which indirectly reduces the production cost of green hydrogen.
Green hydrogen is no longer "unattainable", and the production of hydrogen through electrolysis of water through photovoltaic power generation not only achieves no carbon emissions in the production process, but also achieves zero carbon emissions in the use process, achieving truly double the clean. It is believed that with the further maturity of future technologies, "green hydrogen" will become one of the important and major new energy sources in the future, and contribute more to the realization of the dual carbon goals.

In the field of energy storage batteries, 51.2V 200Ah is a common specification in home energy storage systems. For users, understanding the actual energy storage capacity (i.e. kWh) of this parameter is the key to evaluating system performance. Based on GreenMore's professional experience and combined with the technical standards of the energy storage industry, this article will analyze the energy calculation logic of 51.2V 200Ah batteries and explore their value in different application scenarios.

• Energy calculation method for 51.2V 200Ah battery

The energy storage capacity of a battery is usually measured in kilowatt-hours (kWh), while ampere-hours (Ah) and volts (V) are the basic parameters for describing battery capacity. The conversion formula between the three is:

Energy (kWh) = Voltage (V) × Capacity (Ah) / 1000

​Take GreenMore's 51.2V 200Ah lithium iron phosphate battery as an example:

Energy = 51.2V×200Ah/1000 =10.24kWh

This result means that the battery can store 10.24 kWh of electricity when fully charged, which is enough to meet 10-15% of the average household's daily electricity demand (taking an average daily electricity consumption of 60-80 kWh as an example).

• Why is energy storage battery capacity measured in kWh?

      1. Directly related to the electricity price system

         The global electricity market generally uses "kWh" as the billing unit. When users use energy storage systems to achieve peak-valley electricity price arbitrage or off-grid power supply, kWh can directly quantify economic benefits. For example, GreenMore's home energy storage system can help users release 10.24kWh of energy charged during valley power hours during peak power hours, saving electricity expenses.

      2. Compatible with photovoltaic and inverter systems

The 51.2V voltage design is suitable for mainstream 48V photovoltaic systems (such as 5kW-10kW inverters), and the kWh indicator directly reflects the matching degree between the system and photovoltaic power generation. For example, GreenMore's stacked energy storage module supports multiple machines in parallel. Users can flexibly expand to 30.72kWh (3 sets of 51.2V 200Ah batteries in parallel) according to the rooftop photovoltaic installed capacity (such as 15kW), achieving 100% self-consumption of photovoltaic power generation.

      3. Comply with international standards and certification requirements

International certification systems such as UL and IEC require energy storage equipment to clearly mark the kWh energy value to ensure safety and compatibility. GreenMore's 51.2V 200Ah battery has passed UN38.3, CE and other certifications, and its 10.24kWh energy parameter has become the core basis for overseas customers' purchasing decisions.

• Impact of technical parameters on practical applications

      1. Cycle life and energy decay

GreenMore's lithium iron phosphate battery has a cycle life of 6,500 times (80% DOD), which means that the 10.24kWh initial energy can still maintain more than 80% after long-term use. For example, the Colombian household energy storage project uses 51.2V 200Ah batteries, which are charged and discharged once a day. After 10 years, it can still provide 8.19kWh of effective energy, significantly reducing LCOE (levelized cost of electricity).

      2. Effect of temperature on energy efficiency

In low temperature environments, the internal resistance of the battery increases, resulting in a decrease in available energy. GreenMore's temperature-controlled lithium battery technology can extend the operating temperature range to -20°C to 60°C, ensuring that a 51.2V 200Ah battery can still release more than 90% of its nominal energy (about 9.22kWh) at -10°C, which is suitable for household energy storage needs in high-cold areas.

      3. Parallel scalability and system redundancy

Through modular design, GreenMore's 51.2V 200Ah battery supports unlimited parallel connection. For example, the Ethiopian hotel energy storage project uses 20 groups of batteries in parallel with a total capacity of 204.8kWh, which can achieve millisecond-level load switching with the EMS system to ensure power supply reliability.

• How do users choose the appropriate energy storage capacity?

      1. Home energy storage scenario

      2. Commercial energy storage scenarios

• GreenMore's technical advantages and cases

As a professional energy storage battery manufacturer, GreenMore's 51.2V 200Ah battery has the following differentiated competitiveness:

1. High energy density: The volume energy density reaches 160Wh/kg, which is 300% higher than traditional lead-acid batteries and saves more than 50% of installation space.
2. Intelligent BMS system: real-time monitoring of battery status, supporting SOC (remaining power) accuracy ≤2%, avoiding the risk of overcharging and over-discharging.

Case: A German household photovoltaic energy storage project uses GreenMore's 51.2V 200Ah battery, paired with a 10kW photovoltaic system, to achieve an average daily power generation of 40kWh, of which 25kWh is stored in the battery. The proportion of self-use electricity has increased from 30% to 85%, reducing carbon emissions by 12 tons per year.

In summary, the 10.24kWh energy of the 51.2V 200Ah battery is not only a reflection of technical parameters, but also GreenMore's commitment to the economy, reliability and sustainability of energy storage systems. Whether it is a household user pursuing a green and low-carbon life or a corporate customer optimizing energy costs, choosing GreenMore's energy storage solution can maximize energy value.

Contact the GreenMore team now or visit www.gmsolarkit.com to get customized energy storage solutions and start your energy transformation journey!