Ireland RESS 6: project monitoring and auction dates

Ireland's Renewable Electricity Support Scheme provides financial support to grid-scale renewable electricity projects. Support is allocated through competitive auctions. RESS 6 is the sixth onshore competition.

Projects above 50 kW that fall below the grid-scale auction route should also assess the separate Small-Scale Renewable Electricity Support Scheme, which uses an export tariff rather than a competitive auction.

The auction and the electricity connection are different workstreams. A project can qualify for an auction and still have connection, commissioning and operating conditions to meet. Conversely, operational meters and controls that satisfy the connection design do not qualify the project for RESS support. Keep the auction documents, connection agreement, Grid Code evidence, settlement arrangement and plant operating record as separate controlled sets.

Current RESS 6 dates

EirGrid published revision 1.3 of the final auction timetable on 6 October 2026. It changed the final application withdrawal and qualification-decision submission dates. These are the remaining milestones in that version.

The timetable says it must be read with the RESS 6 Terms and Conditions, amendments and auction parameters. A project team should link to the live EirGrid RESS page in its controlled register rather than copying dates into an unmaintained spreadsheet.

What RESS support does

RESS is a competitive support scheme for renewable generation. The Department describes the auction as a simple sealed-bid process in which eligible offers are selected from the lowest price until the quantity sought is reached. The support price acts as a minimum and maximum: when the market reference is below it, the project receives support; when the market reference is above it, the project pays the difference back under the scheme rules.

The qualification pack gives bid-bond examples for onshore wind, solar, wind and solar hybrids, and wind and solar hybrids with storage. Those examples use deemed energy quantities and technology capacity factors for the bond calculation. They do not establish the complete eligibility or operating rules. Use the current Terms and Conditions and Auction Information Pack for decisions about a specific project.

Three measurement records, three purposes

A renewable project can have several meters that report different values without any of them being faulty. The project should state which record owns each decision.

Do not advertise an ordinary Modbus meter as a RESS meter. Whether a device can be used for settlement, a Grid Code test or a protection function depends on the applicable rules, approved design, accuracy class, time synchronisation, installation and verification. EpiSensor equipment provides operational evidence and integration around those systems.

A monitoring plan for solar, wind and hybrid sites

Start at the physical boundaries.

1. Grid connection. Measure import and export at the agreed connection point. Record phase power, voltage, current, power factor and frequency. This is the reconciliation anchor, even when it is not the settlement meter.
2. Generating units. Record output, availability, operating state, active limit, reactive set point, alarms and communications health for each inverter, turbine or plant group.
3. Auxiliary consumption. Separate transformer, heating, cooling, pumps, controls and other station service loads. Gross generation and net export are not interchangeable.
4. Weather reference. For PV, record irradiance and module or representative cell temperature. For wind, use the project's approved meteorological and turbine records. A weather signal explains resource variation; it is not a substitute for energy measurement.
5. Storage. Record AC power at the battery boundary, state of charge, available charge and discharge limits, operating mode, command, command acknowledgement and measured response.
6. Limits and curtailment. Record the active limit and its source, such as the plant controller, connection-point export limit, system operator instruction, equipment protection or state-of-charge constraint.

Use the same sign convention and time base throughout. At each interval, test a simple balance:

generation + battery discharge + grid import = grid export + battery charge + auxiliary consumption + losses

The equality will not be exact because meters have different classes, timestamps and locations. Define the expected tolerance and investigate a persistent residual rather than forcing the totals to match.

Hybrid projects need a control ledger

A hybrid site can share a grid connection while wind, solar and storage have separate commercial and technical constraints. At any instant, the plant controller may choose among curtailing solar, curtailing wind, charging the battery or reducing total export.

Record each control action as four linked events:

• the instruction and its source;
• acceptance by the target controller;
• fresh device feedback showing the resulting state;
• independent power measurement at the asset and connection boundaries.

An accepted set point proves that a controller received a request. It does not prove delivery. A battery may reach its state-of-charge limit, an inverter may be temperature limited, or a protection relay may have removed a feeder. The BESS command-verification guide gives the complete test pattern.

Data-quality acceptance before operation

Before using an operational dashboard as project evidence, run these checks.

• Match each meter, inverter, turbine, battery and sensor to an exact asset identifier and drawing reference.
• Check current-transformer ratio, phase order, direction and sign with a known import and export condition.
• Compare device totals with local displays and the independent connection-point meter over a complete operating day.
• Confirm units, scale factors and signed values against the manufacturer interface document for the exact model and firmware.
• Record the clock source, time zone, interval close convention, expected latency and handling of a missing interval.
• Cause one known alarm and one communication loss. Confirm their timestamps, ownership and recovery state.
• Test every enabled control with the asset owner, documented interlocks and an agreed safe fallback.
• Preserve configuration, firmware and register-map versions with the commissioning record.

These checks support reliable operation and faster fault investigation. They do not certify the project for RESS 6 or its grid connection.

Where EpiSensor fits

EpiSensor can provide independent three-phase measurement at the connection point and asset feeders, collect environmental and auxiliary data, and integrate documented Modbus or BACnet points through an on-site Edge Gateway. Local storage preserves the operating record during an upstream outage, while APIs and protocols can serve the collected data to the owner's platform.

The useful outcome is a reconciled operational record: what the resource could produce, what limit applied, what command was issued, what the plant reported and what power actually crossed each boundary. The project still uses its approved settlement meter, protection, system-operator interface and compliance tests.

For the first survey, map the boundaries with the solar PV monitoring guide or battery demand-response guide. Use the System Builder to identify monitoring interfaces after the project measurement plan is agreed. Sites that plan to aggregate demand, generation or storage for system services should also use the Irish DSU and system-services guide to define availability, real-time signals and event evidence.