A 750kW solar project can produce a substantial share of the electricity used by a large factory, warehouse, farm or distribution centre. But the right investment depends on more than panel price. Roof structure, daytime electricity demand, grid connection capacity, grant eligibility and the amount of power exported all influence the business case.
This guide explains how to estimate panel count, roof and land requirements, annual generation and project economics for a 750kW commercial solar system in Ireland. The figures are planning examples, not a design, grant approval or supplier quotation.
What is a 750kW commercial solar system?
The panels’ combined rated output is usually described in kilowatt-peak (kWp), a DC rating measured under standard test conditions. A 750kWp array does not produce 750kW at every moment. Actual output rises and falls with daylight, weather, panel temperature, orientation and system losses.
Inverters convert the panels’ direct current (DC) into alternating current (AC) for the site and electricity network. Inverter capacity is expressed in kW and may differ from the array’s kWp rating. The approved maximum export capacity is a separate grid-connection limit. A battery’s capacity is measured in kilowatt-hours (kWh); its power rating, in kW, describes how quickly it can charge or discharge.
Solar electricity generally serves on-site demand first, subject to system design. When generation exceeds demand, surplus may be exported under an approved connection and commercial export arrangement. When panels produce less than the site needs, the business imports the balance. A battery can store some surplus for later use, but adds cost and is not automatically beneficial.
750kW solar panel count by panel wattage
To estimate the 750kW solar panel count, divide 750,000 watts by the rating of each panel. Where the calculation does not produce a whole number, the table rounds up to the next panel so the total reaches or slightly exceeds the target.
For a 750kWp target, the panel count depends on the wattage of each module:
•400W panels: 750,000 ÷ 400 = 1,875 panels, giving an array of 750.00kWp.
•450W panels: 750,000 ÷ 450 = 1,666.67, so use 1,667 panels to reach or exceed the target. This gives 750.15kWp.
•500W panels: 750,000 ÷ 500 = 1,500 panels, giving an array of 750.00kWp.
•550W panels: 750,000 ÷ 550 = 1,363.64, so use 1,364 panels to reach or exceed the target. This gives 750.20kWp.
The exact project may use a slightly smaller or larger array after the designer accounts for available roof planes, electrical string design, inverter selection and the agreed export limit. Higher-wattage modules reduce the number of panels, but do not automatically reduce roof area by the same proportion because module dimensions differ.
750kW solar roof space and land requirements
SEAI gives an example of a 30kWp PV system using 75 panels over about 125m². If that panel density is scaled directly, a 750kWp array would have roughly 3,125m² of module surface. This is a useful early comparison, not a roof-layout drawing: current modules vary in size, and a designer must use the actual product dimensions.
The total usable roof area needs to be larger than the panel surface. The layout must account for safe access routes, maintenance clearances, roof edges, fire access, roof lights, drains, plant equipment, shading and mounting requirements. As an initial screen only, a business could assess whether it has about 3,900–4,700m² of clear, usable roof. That allowance is not an official standard or guarantee that the structure can support the system.
Before specifying a rooftop array, a structural engineer should assess the roof’s condition and load capacity, including wind forces and the proposed mounting method. Roof age, waterproofing, membrane or metal construction, corrosion and any required repairs can change both the layout and cost. A roof replacement scheduled within the project’s payback period may also affect the investment decision.
For ground-mounted solar, panel surface is only part of the land requirement. Row spacing, access roads, drainage, boundary setbacks, inverters, cable routes and planning constraints all affect the layout. Roughly 0.75–1.5 hectares can be used as an early site-screening allowance for a 750kWp project, not as a statutory rule or a final land estimate. A measured site plan and concept design are needed to determine the actual area.
Estimated annual output of a 750kW solar PV system in Ireland
The European Commission Joint Research Centre’s PVGIS tool estimates solar radiation and PV performance for locations and system configurations. Illustrative PVGIS 5.3 runs for Dublin, Cork and Galway, using a fixed south-facing 1kWp array at 35° tilt and 14% system losses, return about 982, 994 and 926kWh per kWp per year, respectively. Scaled to 750kWp, these examples indicate approximately 695–746MWh per year at those three locations.
These are modelled examples, not a nationwide guarantee or an installer’s production forecast. A low-tilt east–west roof, a different pitch, shading, equipment specifications and system losses can shift the result. Output is also seasonal: summer’s longer days usually deliver more electricity, while winter’s shorter days reduce generation. Irish PV works from daylight rather than heat, but persistent cloud still reduces the available solar energy.
A project forecast should use the site’s coordinates and roof geometry, product specifications, shading survey and realistic loss assumptions. Inverter efficiency, wiring losses, soiling, downtime and clipping also matter. Compare the forecast hourly output with the business’s interval electricity consumption; annual kWh alone cannot reveal the share that will be self-consumed.
750kW solar system cost Ireland: what shapes the price?
There is no single defensible price for every 750kW solar system cost Ireland enquiry. LVP Renewables publicly lists a broad commercial PV installation range of €850–€2,000 per kWp, but its commercial page describes systems from 2kW to 400kW. That published range is therefore not a verified 750kW quotation, and multiplying it by 750 should not be presented as a project price.
A commercial proposal should itemise the solar modules, inverters, mounting structures, DC and AC cabling, switchgear and protection, meters, monitoring, safety equipment, engineering, roof and structural surveys, installation labour, lifting equipment, testing and commissioning. It should also identify whether grid-connection studies, connection works, VAT, maintenance and any battery equipment are included.
The roof type and installation method affect labour and materials. A fragile roof, complex access, long cable routes, roof repairs, structural reinforcement or difficult lifting can add work. Ground-mounted projects may require civil engineering, drainage and access improvements. The local grid can impose export limits or require upgrades; those costs and the connection timetable cannot be known from panel count alone. Battery storage, enhanced monitoring or specialised inverter settings add further investment.
For a reliable commercial solar installation cost, request a site survey and an itemised fixed or clearly scoped proposal. Ask the installer to separate the solar EPC price from network charges and optional storage so alternative designs can be compared on a like-for-like basis.
Commercial solar grants Ireland: SEAI NDMG
SEAI’s Non-Domestic Microgen Grant (NDMG) supports qualifying businesses and other listed non-domestic applicants, including the agricultural sector, public bodies, schools, community centres and non-profit societies. SEAI states that systems up to 1,000kWp can be funded under the scheme, so a 750kWp system is within the published size ceiling. That does not mean every project or applicant qualifies.
As displayed on 14 October 2026, SEAI lists €300 per kWp for systems in the 201–1,000kWp band. At 750kWp, that band calculation is €225,000. SEAI also states that, for new applications made from 6 October 2026 through 6 July 2027, the enhanced effective grant is 45%; the amount paid is the lower of the figure on the application summary and 45% of the invoiced cost. In practice, the €225,000 figure is subject to that invoice limit and every other scheme condition. It is not a guaranteed award.
SEAI’s application steps require an applicant to select a registered Non-Domestic Microgen solar company and agree a formal contract before applying. The applicant should receive the grant offer before work starts. The installer applies to ESB Networks before installation, and SEAI’s page states that the application process takes at least 20 working days. Grant offers are valid for eight months. Applicants should check the live scheme terms and required documents before committing to a financial model. Existing applications are not increased under the new rate, and the enhanced application window has an end date.
Other tax or sector supports may be relevant to particular businesses, but this guide does not assume that they apply or can be combined with NDMG. Confirm any separate support and tax treatment with the relevant authority and the business’s tax adviser.
Savings, export income and commercial solar return on investment
Solar’s value depends on the share of output used on site. Electricity consumed as it is generated can reduce imports at the business’s avoidable unit rate. Surplus electricity may earn an export payment, but the rate and contract depend on the supplier and project arrangements. Do not assume a household export tariff applies to a 750kWp generator.
A simple annual value estimate is:
Annual net benefit = (solar used on site × avoidable import rate) + (solar exported × export rate) − operating and maintenance costs.
Here is an illustrative calculation, not a current market-price forecast. Assume 750kWp generates 720MWh in a year, the business self-consumes 70%, its avoidable electricity price is €0.20/kWh, exported electricity earns €0.08/kWh, and annual operation and maintenance costs are €9,750. These rates, output and costs are assumptions and must be replaced with the site forecast, electricity contract and maintenance proposal.
Under those assumptions, on-site consumption is 504MWh, worth €100,800. The remaining 216MWh earns €17,280 at the assumed export rate. After €9,750 of maintenance, the modelled annual net benefit is €108,330. If an actual project quote were €975,000 and the business received the full €225,000 grant used in this example, net investment would be €750,000 and simple payback would be about 6.9 years (€750,000 ÷ €108,330). The €975,000 project cost is only a scenario input—not a verified 750kW market price—and the grant is not assured.
Simple payback excludes financing, tax, inflation, grant-payment timing, panel degradation, inverter replacement, downtime and future changes in import or export prices. A robust commercial solar return on investment assessment should model several cases for self-consumption, prices, production, capital cost and grant award rather than rely on one headline payback period.
Is battery storage suitable for a 750kW solar system?
A battery may help when a business has a consistent midday solar surplus and valuable demand later in the day. It can shift some electricity to evening operations, provide certain resilience services if designed for that purpose, or help manage a constrained export limit. The battery must be designed around the business’s load profile and the export agreement.
Storage adds battery cells, a battery inverter or power-conversion system, controls, fire-safety provisions, installation and replacement considerations. Its energy capacity is in kWh and its power rating in kW. A battery can reduce exports, but it does not create extra solar energy; conversion and storage introduce losses. Compare the extra investment and replacement profile with the value of the energy shifted before adding storage to the base PV proposal.
Main components and suitable businesses
A 750kWp installation typically includes PV panels, a mounting system, DC cabling and isolators, inverters, AC switchgear and protection, generation and export metering, monitoring, safety labelling and shutdown arrangements, and the approved grid-connection equipment. Batteries are optional and should be specified separately.
Potential sites include factories, warehouses, distribution centres, agricultural facilities, food processors and other large industrial premises. Suitable businesses usually have a roof or site with adequate space, a structurally viable mounting area, manageable shading and a load profile that can use a material share of generation. A high annual electricity bill alone does not guarantee a good fit.
Planning, grid connection, safety and installation timeline
Start with electricity bills and interval data, a site and roof survey, structural checks, shading assessment, concept layout and a review of export needs. The final design should state array capacity in kWp, inverter capacity in kW, forecast annual kWh and proposed maximum export capacity.
Planning requirements depend on the property, location and applicable exemptions. Confirm the position with the local planning authority or project advisers rather than assuming a blanket exemption for every commercial roof or ground-mounted system.
ESB Networks states that a single generator application with maximum export capacity below 40MW should first be submitted to ESB Networks for distribution-level connection. Its guidance includes generator application documents, a site plan and single-line diagram requirements, plus capacity and connection-cost tools. This route does not establish that the local network can accept 750kW of export. The connection design, export limit, protection requirements, network studies and any upgrade works are site-specific.
The installer should coordinate grid application and approvals, electrical design, safe isolation, installation, testing, commissioning, metering and handover. SEAI says the grant-linked network application must be made before installation and that the connection application takes at least 20 working days; larger or constrained projects may take longer. A realistic programme depends on survey findings, planning checks, grant approval, network decisions, equipment lead times and site works. No fixed overall timeline should be promised before those steps are understood.
Warranties, maintenance and long-term performance
Panel product and output warranties are not the same as inverter or mounting-system warranties. Review the term, exclusions and claims process for each component. Ask who monitors faults, who performs inspections and what response times are included.
Routine operations may include checking monitoring alerts, inspecting electrical and mounting equipment, keeping access routes and drains clear, and cleaning only when site conditions and manufacturer guidance warrant it. Monitoring allows actual output to be compared with the forecast and can help identify faults early. Financial forecasts should allow for long-term performance change, inverter replacement and any maintenance contract.
LVP Renewables’ current commercial page describes rooftop and ground-based PV and systems from 2kW to 400kW. As 750kW is above that stated range, a business should confirm directly whether LVP can assess and deliver a project at this scale. For a tailored commercial solar assessment, businesses can contact LVP Renewables to discuss energy consumption, roof space, connection requirements and a project quotation.
FAQs
How much does a 750kW solar system cost in Ireland?
There is no verified standard price for a 750kW installation. Roof type, equipment, labour, grid works and site complexity all affect the cost. LVP publishes a broad commercial PV range of €850–€2,000/kWp, but its page describes systems up to 400kW, so that range should not be treated as a 750kW quote.
What commercial solar grants are available in Ireland for a 750kW installation?
SEAI’s NDMG supports qualifying non-domestic applicants and allows systems up to 1,000kWp. At 750kWp, the displayed band calculation is €225,000, subject to the invoice cap, application timing and full scheme eligibility. Confirm live terms with SEAI; funding is not automatic.
How many solar panels are needed for a 750kW solar system?
Approximately 1,875 panels at 400W, 1,667 at 450W, 1,500 at 500W or 1,364 at 550W. The final count can vary slightly with the array design.
How much electricity can a 750kW solar system generate annually in Ireland?
The illustrative PVGIS results for Dublin, Cork and Galway indicate about 695–746MWh per year for a 750kWp fixed south-facing array at 35° tilt with 14% system losses. Actual production depends on location, roof layout, shading and system design
