IN Brief:
- Los Maitenes combines approximately 131MWp of solar with a 90MW/360MWh battery.
- A long-term power purchase agreement covers daytime and night-time delivery blocks.
- Commissioning is targeted for September 2027 in Chile’s O’Higgins region.
ContourGlobal has started construction of the Los Maitenes hybrid power project in Chile, combining approximately 131MWp of photovoltaic generation with a 90MW/360MWh battery energy storage system.
The facility is being developed in the O’Higgins region, extending ContourGlobal’s Chilean solar and storage portfolio from the country’s northern renewable zones towards a major centre of electricity consumption.
The battery has a nominal four-hour duration, allowing it to discharge at its full 90MW rating for approximately four hours before reaching its stated 360MWh energy limit. That configuration is intended to shift solar electricity from daylight periods into later hours when photovoltaic generation is unavailable.
Los Maitenes has secured a long-term power purchase agreement covering daytime and night-time delivery blocks. The remaining production will be exposed to merchant-market opportunities, giving the operating system a combination of contracted obligations and market-driven dispatch.
ContourGlobal’s project page targets commissioning in September 2027. The company has not published a more detailed programme separating first energisation, battery testing, contractual delivery, final completion, and commercial operation.
Hybrid design changes the role of a solar project within the electricity market. A conventional photovoltaic plant exports when sunlight is available, subject to its connection limit and curtailment instructions. A solar-plus-storage facility can export immediately, charge the battery, or divide available output between both routes.
That decision requires a control system coordinating photovoltaic inverters, battery power-conversion equipment, the plant controller, substation, market schedules, contractual commitments, and state of charge.
The battery must retain enough energy to meet night-time delivery while avoiding unnecessary curtailment during the day. Charging too early can leave insufficient capacity for a later solar surplus, while charging too late can leave the system unable to fulfil its evening obligation.
Forecasting is therefore central to the operating model. Solar irradiance, temperature, plant availability, electricity demand, transmission conditions, market prices, and battery efficiency all influence the charging and discharge schedule.
The four-hour duration gives Los Maitenes more flexibility than a short-duration battery designed mainly for rapid frequency services, although it may still provide faster grid support where equipment and commercial arrangements allow. ContourGlobal has not disclosed the final service mix.
Chile has developed large volumes of renewable generation in regions distant from several principal consumption centres. Transmission congestion and periods of surplus solar output have increased the risk that available renewable energy cannot be delivered when it is generated.
Los Maitenes is positioned closer to the central demand area than ContourGlobal’s northern projects. That location is intended to reduce exposure to some transmission constraints, although no plant is insulated from network congestion or changing system conditions.
A battery can mitigate curtailment only when it has unused charging capacity at the required time. Once fully charged, the project faces the same export limit as another generator unless electricity can be consumed locally or the network has available capacity.
The 90MW battery power rating also means it cannot absorb the full 131MWp theoretical solar output if the grid accepts no export. Actual alternating-current output will differ from the module nameplate rating, but the controls must still manage periods when generation, charging capacity, and the connection limit do not align.
Detailed design will cover the photovoltaic array, module and inverter configuration, medium-voltage collector system, battery containers, power-conversion systems, transformers, switchgear, protection, control, communications, fire detection, thermal management, and emergency response.
The battery introduces a different risk profile from the solar plant. Cell monitoring, cooling, gas detection, electrical isolation, fire compartmentation, drainage, access control, and coordination with local emergency services must be integrated into construction and operation.
Commissioning will be more involved than energising a standalone photovoltaic facility. Individual battery blocks and inverters must be tested before the combined system demonstrates charge and discharge power, usable energy, efficiency, response time, controls, communications, and compliance at the connection point.
Long-term performance will depend on degradation management. Battery cells lose usable capacity through time and cycling, requiring operating limits, warranties, augmentation, or replacement strategies to maintain contracted night-time delivery.
ContourGlobal has not identified the battery cell supplier, power-conversion provider, photovoltaic module manufacturer, main contractor, connection voltage, or augmentation plan. Those disclosures will define more of the project’s technical character as construction advances.
Los Maitenes follows ContourGlobal’s Quillagua and Victor Jara hybrid projects in Chile. The company describes those northern assets as combining 452MWp of photovoltaic generation with 400MW of battery power and 2.5GWh of storage capacity, while Los Maitenes adds another four-hour system in the centre of the country.
Generation capacity and storage power are not interchangeable measures. A battery does not create primary energy; it absorbs electricity, retains part of it after conversion losses, and returns it at a more useful time. Its value lies in controllability, timing, and system support.
Los Maitenes will test whether contractual design, location, solar generation, and four-hour storage can be combined into a dependable supply profile. Construction has begun, but the night-time delivery proposition will be demonstrated only after the battery, controls, connection, and power purchase agreement operate together under real grid conditions.
