Maharashtra's 2026 ToD and Energy Banking Changes: What Do They Mean for Renewable Project Economics?

Why daytime solar no longer offsets your evening bill, and what it changes for project economics.

For grid-connected renewable projects, the commercial value of generation depends on more than a project's annual energy yield. A solar project typically generates most of its energy between 09:00 and 17:00, while consumer demand can continue into the evening. The ability to bank surplus generation and use it when required is therefore an important part of the project's economics.

Maharashtra's revised tariff framework changes this. The Maharashtra Electricity Regulatory Commission's order in Case No. 75 of 2025 (March 2026) revised the time-of-day (ToD) and banking provisions that apply to consumers across the state's distribution licensees. These provisions distinguish between the periods in which energy is banked and the periods in which it can later be drawn back.

The Time-of-Day Slots

The banking rule sits on top of Maharashtra's time-of-day (ToD) tariff structure, which divides the day into four periods priced according to system demand and the availability of low-cost solar. The banking rule can only be understood against these slots, because energy is banked and drawn within these time periods.

The daytime solar window carries the lowest tariff, reflecting abundant low-cost solar on the system. The evening peak carries the highest tariff, reflecting the point at which solar generation has declined, and the grid relies on costlier generation to meet demand. The two normal periods, overnight and early morning, sit in between.

How the Banking Rule Works

The treatment of banked energy varies by ToD slot. Energy banked in one slot can be used in that slot or in a lower-tariff slot, but never in a higher-tariff one. This is set out in Regulation 20.3 of MERC's Distribution Open Access Regulations.

Applied to the four slots, this produces an asymmetric matrix.

Because the daytime window is the lowest-tariff slot, energy banked there can only be drawn back during the same daytime hours. It cannot be carried into the evening peak or into the overnight and morning periods, regardless of the technology that generated it. By contrast, energy banked during the evening peak slot can be used in any ToD slot.

Who the Rule Applies To

The rule does not apply to every renewable consumer in the state. It applies to non-residential consumers in the MSEDCL area, while some residential rooftop consumers may be exempt from the ToD slot-wise banking restriction depending on the applicable load category.

The framework applies to renewable energy generated by solar, wind and hybrid projects. The banking rules are determined by when the energy is injected and when it is subsequently drawn, not by the source. What makes the change appear solar-specific is the generation profile. Solar generation is concentrated in the daytime window, which is the lowest-tariff slot, so energy banked during those hours faces the greatest restriction on when it can be drawn.

What It Does to Project Economics

The change reaches beyond the electricity bill of the consumer taking the power. It alters the economics on which renewable projects are developed, contracted and financed. For developers, this means reassessing expected revenues, savings and returns based on generation profile, the offtaker's load curve, and the applicable banking treatment under the revised ToD framework.

For the offtaker, the immediate question is how much of the contracted renewable generation can actually offset its consumption across the day. Where surplus generation cannot be carried into a higher-tariff period, the project may deliver less effective savings than a model based on unrestricted banking would suggest. This may also lead some consumers to reassess whether the existing billing and renewable supply arrangement remains economically preferable.

The financing implications follow from the same change. Lenders and investors assess a project's ability to generate the cash flows assumed in its financial model. If those assumptions depend on banking arrangements that are no longer available, the project's projected cash flows, returns and risk profile have to be reassessed. Existing projects may therefore need to be tested against the banking treatment under which they were originally financed, while new projects will need to incorporate the revised treatment from the outset.

The economic assessment must consider the interaction between generation timing, offtaker demand, banking treatment and contractual structure. Where those elements do not align, the project may need to bridge the timing gap through direct consumption, load shifting, storage, firmed supply or a combination of these.

What the Change Means in Practice

The impact is more direct for onsite net-metered consumers, who have fewer options to use surplus daytime generation later in the day. The change also affects open-access consumers who have already executed contracts, where projects were sized against their overall consumption, including off-peak ToD slots. For new OA arrangements, offtakers now have greater clarity to choose between solar, wind, or hybrid models to meet demand based on their load and consumption patterns across the day.

For renewable projects, this moves the assessment beyond annual generation and contracted tariffs. The generation profile, the consumer's load, the flexibility to bank energy, and the cost of meeting demand outside the available banking periods now must be considered together.

Where Storage Comes In

For existing projects, the revised ToD and banking framework makes the alignment between renewable generation and demand a project-level consideration, particularly where surplus generation cannot be banked into the hours in which it is required. On-site storage becomes one of the options to assess in the project's operating and economic model, alongside round-the-clock supply and load-shifting. For new renewable projects above 100 kW, the question is settled by rule, Maharashtra's separate Renewable Energy & Energy Storage Policy requires storage to be built into the project from 1 April 2026.

The two measures point in the same direction from different sides. The banking rule removes the grid's role as a free time-shifting mechanism for renewable energy, while the storage policy requires the physical means to time-shift it instead. The combined effect is that matching renewable generation with demand becomes an important part of project design and economic assessment.