The crux of new energy distribution and storage lies in whether the technology is safe, whether the cost can drop rapidly, how to build a business model, and how to strictly control the boundaries of energy storage investment.

Energy storage is the stronghold of the energy industry, and it is also the weakest link currently. Energy storage is booming, and the new energy power system can be prosperous.

New energy has natural fluctuating properties. Although new energy storage can not change the gene of new energy, it can improve the power output characteristics of new energy. From an economic perspective, new energy investment in energy storage also pays for the negative externalities brought to the power system. The crux of the problem lies in how to recover energy storage investment, whether energy storage technology is safe, whether energy storage costs can drop rapidly, how new energy companies innovate industrial forms, build new business models, and how to define the boundaries of energy storage investment.

In the past 15 years of large-scale development of domestic new energy, financial subsidies, national planning and other policy dividends have been the main driving forces for the development of the industry. On the other hand, power grid systems, thermal power companies, and end consumers have also made concessions for the development of new energy. New energy has a golden spoon from the day it is developed, and under the new low-price ecology, it needs to climb one new hill after another.

Exploration of energy storage business model

Judging from the current business model, the path of value creation for new energy distribution and storage projects includes: (1) Participating in auxiliary services such as peak shaving and frequency modulation, obtaining compensation for auxiliary services, (2) reducing the amount of abandoned wind and photovoltaic power, and increasing electricity costs Income, (3) Reduce grid cost assessment, (4) Participate in electricity market transactions to obtain electricity price income, (5) Others.

According to the deterministic ranking of the above-mentioned profit model, ancillary service income> income from abandoning wind and photovoltaic energy> reducing power grid expenses assessment> others.

Among them, the participation of new energy distribution and storage in auxiliary services of the power system is the most definite mode of profit. At present, 16 provinces and regions have issued a compensation mechanism for peak shaving auxiliary services. Energy storage power stations can provide auxiliary services such as frequency modulation, peak shaving, voltage regulation, backup, and black start for the operation of the power system, and obtain corresponding compensation benefits. At 0.5 yuan/kWh.

In June 2019, the Northwest Regulatory Bureau of the National Energy Administration issued the “Qinghai Electric Power Auxiliary Service Market Operation Rules (for Trial Implementation)”, clarifying that when the power grid requires peak-shaving resources, the energy storage peak-shaving price is tentatively set at 0.7 yuan/kWh, priority Consumption of wind power and solar power generation. On May 26, 2020, Xinjiang Development and Reform Commission issued the “Interim Regulations on Energy Storage Management on the Generation Side of Xinjiang Power Grid”, which compensates for the amount of electricity charged by electric energy storage facilities that enter the charging state according to the instructions of the power dispatch agency. The compensation standard is 0.55 yuan/kW. Time.

From the perspective of the application of energy storage power stations, the Qinghai shared energy storage project Luneng Haixi 50MW/100MWh energy storage power station is a sample. The project was officially put into trial operation on June 18, 2019, and by July 2020, the accumulative charging power was 28.15 million kilowatts At the time, the peak shaving cost was 15.64 million yuan, and the unit price was 0.56 yuan/kWh.

According to the calculation of the number of charge and discharge times of the energy storage battery in the full life cycle of at least 6000, the energy storage power station needs to coordinate with the grid company to ensure that it is fully charged and discharged at least twice a day.

However, in the actual operation process, the new energy storage dispatching power is managed by the power grid company, and it cannot be jointly dispatched with the new energy power station. The new energy developer cannot obtain the auxiliary service income, and the income is unstable.

Another business model of new energy with energy storage is to reduce curtailed wind power through energy storage, discharge it during non-limit periods, or consume it locally. This model is suitable for areas with high on-grid electricity prices and high rates of abandonment of wind and light. As the process of parity for new energy grids accelerates, it is increasingly difficult to obtain investment income from abandonment of electricity.

The reduction of power grid assessment costs is a manifestation of the new value of energy storage. At present, in accordance with the requirements of the “Two Rules” (“Power Plant Grid-connected Operation Management Implementation Rules” and “Grid-connected Power Plant Auxiliary Service Management Implementation Rules”) requirements for grid companies, new primary frequency modulation and virtual inertia responses to wind farms and photovoltaic power plants Functional assessment standards. New energy can reduce grid assessment costs by configuring energy storage.

In addition, new energy distribution and storage can obtain electricity price income through electricity market transactions, but in this mode, electricity prices fluctuate, electricity demand is large, and project income uncertainty increases. In addition, new energy storage power stations can explore integration with user services, charging piles, green certificate transactions, etc., and extend to downstream applications.

However, it should be noted that the energy storage system can only choose one of the business models at the same time of operation, and cannot have both. Therefore, project investment economic estimation needs to take into account different operating modes, and project cash flow inflow needs to be measured according to different scenarios.

Strictly control the economic boundary of energy storage investment

Under the current business model, the economics of new energy distribution and storage are more sensitive to investment costs. The cost of energy storage projects depends on two aspects, one is the ratio of new energy storage, and the other is the cost of the energy storage engineering system. For energy infrastructure, the investment recovery period of the project is within seven years, which has good investment value and can meet the internal income requirements of about 8% of the project.

Regarding the reasonable proportion of new energy distribution and energy storage, PowerChina Northwest Survey and Design Research Institute believes that from an economic point of view, in order to smooth the short-term fluctuations in new energy output, the energy storage capacity can be 10% of the installed capacity of new energy, and the energy storage period It can be designed according to 0.5h~1.0h.

At present, judging from the requirements for new energy storage projects in various regions, the energy storage ratio is between 10%-20%, and the energy storage period is 1 hour to 2 hours. The high ratio of energy storage ratio increases the pressure on investment recovery. .

From the perspective of energy storage cost structure, energy storage power station has three main components, energy storage battery system, energy storage power conversion (PCS) and boost system. Among them, energy storage battery investment accounts for the highest proportion, at about 60%. The cost of the energy storage system has dropped from 2 yuan/wh at the beginning of the year to the current 1.5-1.6 yuan/wh. The focus of energy storage cost reduction is still in energy storage batteries. Reducing the cost of energy storage batteries requires research in technical dimensions such as low attenuation, long life (more than 10,000 cycles), and high storage efficiency (>98%), while reducing Project land cost and operation and maintenance cost.

According to the learning curve of cost reduction, the ideal energy storage cost reduction route is to reduce the cost of the battery system to 50% of the current by 2025, double the scale of energy storage, and reduce the cost of the energy storage system to about RMB 0.8/wh. Driven by technological progress, the slope of cost decline may accelerate.

Scale is an important channel to promote cost reduction. The State Grid Integrated Energy Service Group has established a joint venture company with Ningde Times-State Grid Times Energy Storage Development Co., Ltd., with the purpose of promoting the construction of GW-type energy storage power stations. According to media reports, State Grid will build a total of 1GW/4GWh of electrochemical energy storage power stations in Qinghai, Xinjiang, and Henan provinces, and Qinghai, Xinjiang, and Henan will build 0.3GW/1.2GWh, 0.3GW/1.2GWh, 0.4GW/1.6GWh, respectively. ; At the same time, a single GW energy storage project will be built in Shanxi and other places. The promotion of large-scale energy storage power stations is expected to effectively reduce the cost of energy storage.