In the energy storage industry, PCS, or Power Conversion System, energy storage converter.
Battery storage is usually divided into three major application scenarios: large storage, commercial and industrial storage, and household storage, and the corresponding PCS/inverters in different scenarios are also very different. This article distinguishes PCS for large storage, PCS for industrial and commercial storage, and PCS for household storage from four broad categories: power scale, application scenarios, technical requirements, cost and price, respectively.
I. Power Scale
Large storage PCS:
Power level is high, usually in the MW (megawatt) level, can be as high as 100MW or even higher. Large-scale energy storage systems can store up to several megawatt-hours or even hundreds of megawatt-hours of power to match the large-scale grid energy storage needs, to achieve grid frequency regulation, peak shifting and other functions.
Commercial and industrial storage PCS:
The power is generally between tens of kW (kilowatts) and several MW. Applicable to industrial and commercial users, the storage capacity ranges from several hundred kWh to several thousand kWh, which is used to cope with peak tariffs and meet power reliability requirements.
Household Storage PCS:
Relatively small power, usually between a few kW and a dozen kW. Mainly serving household PV power generation storage and emergency power, household energy storage system capacity is generally in the range of a few kWh to tens of kWh.
II. Application Scenarios
Large storage PCS:
Grid-side: balancing the supply and demand of the grid, smoothing the intermittent output of wind power and photovoltaic power generation, and improving the quality and stability of grid power. For example, when a large-scale photovoltaic power station is connected to the grid, it can store excess power during the day and release power at night or on cloudy days.
Supporting large-scale power stations: cooperate with large-scale thermal or hydroelectric power stations to carry out joint frequency regulation, quickly respond to the demand for grid frequency regulation, and improve the frequency regulation performance of the power system.
Commercial and industrial storage PCS:
Peak-shaving and valley-filling: industrial and commercial users store electricity during the trough period of electricity price and release it during the peak period to reduce the cost of electricity consumption. For example, data centers charge at night and discharge during the day to reduce the demand for peak power from the grid.
Emergency power supply guarantee: Provide emergency power support for key equipment of enterprises when the power grid fails, and guarantee the basic operation of enterprises and normal operation of important facilities.
Household Storage PCS:
Household photovoltaic power generation support: works in tandem with the household solar photovoltaic system to convert DC power to AC power for household use, with excess power stored in the battery to improve household energy self-sufficiency.
Emergency Backup Power: Provides basic power security for households during grid outages, maintaining the operation of important appliances such as lighting, refrigerators, and communication equipment.
Ⅲ. Technical Requirements
Large storage PCS:
Conversion efficiency: high conversion efficiency is required, generally above 95%, to reduce energy loss and improve the economy of the energy storage system.
Response speed: It can quickly respond to grid dispatching instructions, adjust charging and discharging power in milliseconds to maintain grid stability.
System compatibility: good compatibility with large-scale energy storage battery systems and complex grid systems, adapting to different battery characteristics and grid access requirements.
Industrial and commercial storage PCS:
Reliability: high reliability, reduce fault downtime, meet industrial and commercial continuous production or operation needs, require a long average fault-free time.
Power Factor Regulation: Effectively regulates power factor, improves power quality for industrial and commercial users, and reduces corporate electricity expenditure through reactive power compensation.
Household storage PCS:
Safety: with a perfect battery management system to prevent overcharging, over-discharging and short-circuiting of batteries to ensure the personal and property safety of household users.
Ease of use: easy to operate and maintain, with a simple and easy to understand interface, easy to install and integrate into the household power system.
Ⅳ. Costs and Prices
Large storage PCS:
Costs are high, with prices likely to be in the thousands of dollars per kilowatt. High power, high complexity technical requirements, and mass production manufacturing result in high R&D, raw material, and production costs, but prices gradually decline with scale effects and technological advances.
Commercial and industrial storage PCS:
The cost and price are between large storage PCS and household storage PCS, and the price per kW may be around 1000 – 5000 Dollars. Price is affected by power, function, brand and other factors, return on investment is an important factor for industrial and commercial users to consider buying.
Household Storage PCS:
The cost is relatively low, and the price per kW may range from a few hundred dollars to about 2,000 dollars. The power is small, the function is relatively simple, with the expansion of the household energy storage market, the price is expected to be further reduced to improve the acceptance of household users.
Large storage PCS for large-scale grid and power station applications, high power, strict technical requirements, high cost; industrial and commercial storage PCS services industrial and commercial peak shaving and emergency, moderate power, heavy reliability, etc., medium cost; household storage PCS for home PV and emergency use, small power, note safety and ease of use, low cost.
Post time: Jan-04-2025