As carbon neutrality becomes a global consensus, variable renewable energy sources such as solar and wind power are developing at an unprecedented pace. According to data from the International Renewable Energy Agency (IRENA), global newly installed wind and solar capacity reached approximately 670 GW in 2024, accounting for 88% of the total global power capacity additions that year, with cumulative installed capacity now representing 35% of the global total. Renewable energy is rapidly becoming the world's primary energy source. However, the construction cycle and physical carrying capacity of grid infrastructure have fallen significantly behind the explosive growth on the power generation side. This "source-grid mismatch" has pushed grid regulation capabilities in many countries to a critical point. Grid operators are revising interconnection guidelines, substantially raising technical thresholds and model simulation verification standards, while curtailment risks are becoming increasingly prominent.
Author: Ke Weiming
Against the backdrop of "carbon neutrality" becoming a global consensus, variable renewable energy sources such as solar and wind power are developing at an unprecedented pace. According to data from the International Renewable Energy Agency (IRENA), global combined new installations of wind and solar reached approximately 670 GW in 2024, accounting for 88% of global power capacity additions that year, with cumulative installed capacity now representing 35% of total global power capacity. New energy is accelerating its transition to becoming the dominant energy source worldwide. However, the construction cycle and physical carrying capacity of grid infrastructure have lagged severely behind the explosive growth on the generation side. This "source-grid imbalance" has pushed the regulatory capacity of power grids in many countries to a critical point. Grid operators have revised grid connection guidelines, substantially raising technical thresholds and model simulation verification standards, while curtailment risks are becoming increasingly prominent.
For the international engineering contracting sector, this contradiction has also translated into tangible operational crises. It not only directly threatens schedule performance and escalates the risk of liquidated damages, but also—due to limited grid absorption capacity—exposes investors' project returns to curtailment losses. Project development difficulty has risen, and certain country markets have entered a stage of stock competition in the short term.
This article analyzes the common patterns of grid bottlenecks in typical countries worldwide, explores how to build a "grid compliance" defense line throughout the full project lifecycle, and examines the strategic opportunities presented by grid upgrade and renovation, energy storage, pumped-storage hydropower, and other peaking resources amid the "crisis" of grid constraints, offering recommendations for the sound operation of Chinese enterprises in a complex international environment.
Systematic Challenges in Overseas Renewable Energy Integration: An Analysis
As the installed share of renewable energy grows by leaps and bounds, the operational characteristics of power systems have undergone fundamental changes. The fluctuating nature of intermittent power sources, coupled with the lack of regulatory capacity in existing grids, has made system balancing dramatically more difficult. Specifically, the systematic challenges facing overseas renewable energy integration are concentrated in the following three dimensions.
I. Weak Grid Infrastructure and Aging Equipment
The physical grid structure of a power system forms the rigid foundation for renewable energy integration. In many overseas markets, due to outdated infrastructure construction standards and severe equipment aging, grids commonly suffer from saturated transformer capacity and insufficient backbone transmission lines. This physical weakness directly results in severely inadequate short-circuit capacity at grid connection points, rendering them unable to provide the necessary support for large-scale power electronic equipment integration. In weak grid environments, this ceiling on physical carrying capacity forces grid operators to impose stringent access ratio limits at the planning stage. When multiple plants are connected to an aging grid in a concentrated manner, local voltage instability is easily triggered—and in some cases, completed power stations may be unable to achieve full commercial operation because the connection point strength fails to meet the required standards.
II. Imbalanced Power Source Structure and Insufficient Flexibility Resources
Beyond grid infrastructure, the ability of a power system to accommodate renewable energy depends on the regulatory flexibility of the generation side. In many overseas markets, the national power mix is homogeneous and the proportion of flexibility resources is extremely low, leaving systems generally lacking the compensatory capacity to handle instantaneous power fluctuations. Taking Mongolia as an example, approximately 76% of its installed capacity comes from coal-fired thermal power, mostly old, highly polluting low-voltage units with little peaking flexibility. Such aging units typically have high minimum stable output requirements and slow load ramp rates. If large numbers of renewable plants are subsequently connected, the power system—having lost the physical inertia support provided by rotating machinery—will face a risk of collapse.
III. Imbalance and Mismatch Between Load and Supply
In many overseas markets, there is a notable disconnect between resource distribution and electricity demand, meaning that even if a system has theoretical installed generation capacity, it cannot be converted into effective power supply. On the spatial dimension, geographic distribution imbalances restrict the ability to transmit power outward—high-quality wind and solar resources are typically concentrated in remote areas far from urban and industrial centers. On the temporal dimension, mismatches between supply and demand characteristics intensify system dispatch pressure. The output curves of renewable energy and the load curves of social electricity consumption often exhibit off-peak variations; for example, solar PV reaches its output peak at midday, while social load typically forms an evening peak—creating a clear temporal mismatch between the two.
Impacts on International Renewable Energy Projects and Risk Transmission
Facing overseas renewable energy integration difficulties, host-country grid operators often shift systemic security pressure onto project developers by raising technical entry thresholds. At the owner level, grid connection risks are pushed down to contractors through the blurring of contract boundaries. This risk transmission not only reshapes the responsibility boundaries of EPC works but also imposes stringent coordination challenges on downstream subcontractors and equipment manufacturers. The impact on contractors manifests in the following three aspects.
I. Increased Investment Uncertainty and Extended Timelines in the Development Stage
During the project development stage, driven by curtailment risks and revenue uncertainty, the number of public development projects relying partly on fixed feed-in tariff guarantees has declined, and the market is gradually shifting toward projects with private owners or self-operated market trading. Under such models, electricity prices and curtailment risks are borne more by the project entity itself, further increasing the complexity of decision-making during development. Brazil provides an example: due to the rapid growth of renewables in previous years and slow expansion of transmission infrastructure, the wind and solar curtailment rate surged above 25% starting in 2023. This directly undermined investment return projections, severely damaging the expected financial returns of some projects, and consequently slowed or even canceled project development. As grid connection conditions continue to change and uncertainty grows, the pace of project development is shifting from being driven by resource endowment and land acquisition to being dependent on grid connection capacity and headroom, further extending development cycles. Developers can no longer pursue extensive development as they once did; instead, they must conduct meticulous planning at the front end to address the increasingly severe grid integration challenge.
II. Increased System Complexity in the Design Stage
In the technical design stage, conventional renewable power plants are evolving into multi-system coupled structures of "renewable energy + energy storage + grid support," encompassing design across multiple tiers such as energy management systems, storage control strategies, and grid dispatch interfaces, resulting in significantly higher overall system complexity. Notably, energy storage configuration has become an indispensable component of most projects. However, due to the lack of unified capacity ratios, functional positioning, and configuration standards, owners often fail to clearly define the specific roles of storage in various application scenarios such as peak shaving, frequency regulation, and backup. Taking weak-grid regions in Central and West Africa such as the Democratic Republic of the Congo as an example, the demand for mining-power development is strong, and plant designs must fully account for the load characteristics of different mining areas, matching technical requirements such as peak-load response, reactive power compensation, black start, and islanded operation according to varying power consumption needs. Meanwhile, in some projects, key equipment is often locked in by relevant parties—whether by brand or technology route—at the design stage itself, which to some extent compresses the contractor's technical leadership space in the overall system solution, while the responsibility for overall system performance and grid connection outcomes still rests with the contractor. From a comprehensive perspective, the risks and complexity facing design solutions continue to rise.
III. Concentrated Release of Risks Under Multiple Constraints in the Execution Stage
During the execution stage, the uncertainties accumulated in the development and design stages are released in a concentrated manner. First, the joint commissioning of photovoltaic and energy storage systems involves multi-system coupled control, which is significantly more complex than traditional single-source power projects, making commissioning schedules difficult to control precisely. On top of this, projects must simultaneously satisfy multi-dimensional technical acceptance requirements covering generation performance, storage efficiency, and grid support capability, further increasing uncertainty during execution. In some projects, there are even unreasonable cases of overlapping assessments and duplicate penalties, which significantly amplify contractor risk. In addition, renewable energy projects typically require supporting expansion work on the opposite-side substation. Such works are mostly carried out by shortlist enterprises designated by the grid company or local subcontractors, with extensive use of local labor, meaning the general contractor's control over the schedule and construction quality of critical works is markedly limited. The progress of opposite-side substation construction and grid-side renovation directly determines the readiness of grid connection conditions. Once project progress is hindered, combined with the dynamic tightening of grid connection standards during the implementation period, the original design may no longer meet the latest requirements at the time of connection, triggering design rework, equipment adjustments, or even system reconfiguration. This exposes contractors to additional and unforeseeable liabilities, further intensifying the systemic risks of the execution stage.
Coping Strategies and Key Risk Control Points
Against the current backdrop of increasingly stringent renewable energy integration constraints and significantly heightened grid-side uncertainty, contractors' risk exposure in projects continues to expand. However, limited by resource inputs and business boundaries, contractors find it difficult to comprehensively intervene in project development and system planning. Therefore, they should minimize the impact of uncertainty by strengthening information acquisition, early-stage involvement, and control over critical links. This can be carried out along the following five dimensions.
I. Strengthening Early-Stage Information Acquisition to Identify Hidden Grid Connection Risks
During the development stage, contractors generally find it difficult to independently conduct in-depth system access analysis or integration capacity assessments. Therefore, they should focus on strengthening the acquisition of key information and experience-based judgment capabilities. This requires contractors to pay close attention at the project front end to the substantive progress of grid connection approvals, verify whether formal system access approvals have been obtained, whether the connected capacity is explicitly defined, and whether there are mandatory requirements for grid-side expansion or renovation. At the same time, by gaining an in-depth understanding of the communication basis between the owner and the local grid company, contractors can conduct indirect research into historical curtailment conditions in the region where the connection node is located and the power abandonment phenomena of similar projects already in operation in the same area—thereby building sensitivity to grid connection risks even in the absence of detailed simulation analysis, and identifying hidden constraints that could cause schedule delays or capacity reductions before project launch.
II. Conducting In-Depth Review of PPA Terms to Prevent Downstream Risk Transmission
With the rising share of projects trading in liberalized electricity markets, the revenue uncertainty of renewable energy projects has increased significantly, and related risks often penetrate through to contractors via the contract structure. Therefore, contractors should focus on analyzing the owner's upstream power purchase agreements during the bidding and contract negotiation stages, identifying the assessment requirements concerning generation output and availability, and clarifying the allocation of curtailment responsibility and corresponding compensation mechanisms. Because these terms are often transferred to contractors through EPC contracts, contractors must guard against triggering exorbitant penalties due to grid connection delays or performance indicator deviations. By identifying and avoiding these unclear revenue and liability arrangements, contractors can avoid assuming investment-type risks beyond the scope of EPC works.
III. Proactively Engaging in Equipment Communication to Reduce Passive Integration Risks
In current owner-led project practice, key equipment such as PV modules, inverters, and energy storage systems is often determined by the owner at an early stage. Contractors should therefore proactively adjust their strategies, identify the owner's preferences for specific manufacturers or already-locked technology routes, and establish communication with core equipment manufacturers. By engaging in technical solution discussions as early as possible, contractors can systematically verify the compatibility of equipment performance indicators with grid support requirements, and push for the signing of tripartite agreements among the owner, contractor, and equipment manufacturer—thereby transferring the owner's hard requirements on major equipment, including but not limited to grid connection performance, commissioning schedules, and grid support capabilities, to the manufacturer side.
IV. Dynamically Tracking Grid Policies to Respond to Changing Grid Connection Standards
The dynamic tightening of grid connection standards and technical specifications during the project construction period has become a common feature of the international renewable energy market. Contractors should not only closely monitor local government policies on grid integration and changes in grid connection standards, but also proactively analyze and identify issues in the development of national energy markets, rather than merely responding to owner demands. During engineering design and the setting of key equipment parameters, contractors should maintain an appropriate sense of redundancy, buffering the impact of standard upgrades by reserving a certain technical margin. Through forward-looking information tracking and appropriate redundant design, projects can be ensured to connect to the grid smoothly in a dynamically changing regulatory environment.
V. Strengthening Critical Path Awareness to Monitor External Grid Connection Conditions
During the execution stage, grid connection progress is highly dependent on the completion of opposite-side substation expansion or grid-side renovation works. Contractors must incorporate these external works—over which they have no direct control—into the overall schedule management system. By strengthening communication and coordination with owners, grid companies, and relevant local subcontractors, contractors can continuously track and provide early warnings on external factors that may affect grid connection. Where control is limited, transparent information processing and proactive coordination intervention can minimize risks arising from grid-side delays, ensuring the project is commissioned on schedule.
In summary, the systemic difficulties of overseas renewable energy integration are fundamentally reshaping the competitive rules of international engineering. Facing the performance risks brought by source-grid imbalance, contractors should not remain at the level of passive contract execution. Instead, they should actively capture the market opportunities generated by grid bottlenecks through business transformation. For example, they may position themselves in grid upgrade and renovation businesses to eliminate physical carrying capacity bottlenecks, and leverage their traditional strengths in pumped-storage hydropower and thermal power flexibility retrofits to enhance system regulatory capability by filling the peaking capacity gap. At the same time, for specific scenarios, they should develop mining-power microgrids and integrated source-grid-load-storage projects. In the deep waters of the energy transition, the integration dilemma itself is a beacon of market demand. Only by proactively aligning with market demand can contractors turn crisis into opportunity and achieve steady business growth amid complex international competition.
(Author's affiliation: PowerChina International Group Limited)