Question 1

How big a commercial solar PV system do I need?

Accepted Answer

The right size is driven by your half-hourly electricity consumption profile, not your roof area. We model 12 months of meter data and size the array so daytime self-consumption sits in the 60–85% band — high enough to maximise the value of every kWh generated, low enough to avoid over-sized export that the DNO will not pay much for. As a rough rule of thumb, a UK commercial rooftop generates around 850–1,050 kWh per installed kWp per year depending on orientation, pitch and location.

Question 2

What payback should I expect from commercial solar in the UK?

Accepted Answer

Most commercial rooftop projects in the UK fall in a 4–7 year simple-payback window at current grid tariffs (15–30p/kWh import), with 25+ years of generation life and a typical IRR of 12–20%. Payback shortens when daytime load is high (manufacturing, logistics, hospitality, healthcare) and lengthens for sites with mostly evening demand unless paired with battery storage.

Question 3

Will a solar PV installation disrupt my operations?

Accepted Answer

No — we routinely deliver projects on live, occupied and operational sites including hospitals, hotels, breweries and 24/7 logistics depots. Tie-ins that require a brief power-down are pre-planned with the site team and almost always handled out-of-hours or during a scheduled maintenance window. A full rooftop install on a 250 kWp site typically takes 6–10 weeks on-site, with the cut-over itself measured in hours.

Question 4

How long do commercial solar panels last?

Accepted Answer

Tier-1 modules carry a 25-year linear power warranty (usually guaranteeing ≥ 85% of nameplate output at year 25) and a 12–15 year product warranty. Real-world degradation is around 0.4–0.5% per year. Inverters typically need replacement once at year 12–15. We design every system with end-of-life and recycling routes (PV CYCLE) factored into the long-term cost.

Question 5

Can solar work on a north-facing or shaded roof?

Accepted Answer

Yes, with caveats. East/west splits routinely achieve 85–90% of due-south yield and often suit a commercial daytime load better. Shading is handled with module-level power electronics (SolarEdge optimisers or micro-inverters) so one shaded panel does not drag down a whole string. Pure north-facing pitches above ~10° rarely make commercial sense in the UK.

Question 6

Do I need planning permission for commercial solar PV?

Accepted Answer

Most commercial rooftop solar is permitted development under Class J of the GPDO and does not need planning permission, subject to limits on protrusion above the roof and listed/conservation status. Ground-mount and larger systems (typically > 1 MW or > 9m² on a wall, or in sensitive locations) do need a planning application. We handle the full planning route where required.

Question 7

What roof types and conditions are suitable?

Accepted Answer

Trapezoidal metal, standing-seam, single-ply membrane and good-condition concrete or slate roofs are all suitable. We commission an MCS-aligned structural survey before contract: the roof must have at least 10–15 years of remaining life and adequate residual load capacity. Where a roof needs replacement first, we phase the works together to share scaffold and access costs.

Question 8

When does commercial battery storage actually pay back?

Accepted Answer

Battery storage materially shifts the business case on four site profiles: peaky demand-charge tariffs, export-limited solar sites, high-resilience operations (cold storage, data, manufacturing), and sites that can stack wholesale or flexibility revenue (DSR, FFR, DC). On the right site, storage can double the value of a solar array; on the wrong one, it can wreck the payback. We model it as a separate decision, not a default add-on.

Question 9

What size battery (kW vs kWh) do I need?

Accepted Answer

Size is set by what the battery is being asked to do. Peak-shaving against an MIC or capacity charge is driven by kW (power); time-shifting solar to cover evening loads is driven by kWh (energy); a backup-grade system is driven by both, plus how long you need to ride through. A useful starting point for solar self-consumption is 1–2 kWh of storage per kWp of PV.

Question 10

How long do commercial lithium batteries last?

Accepted Answer

Modern commercial LFP (lithium iron phosphate) systems are warrantied for 10 years and ~6,000–10,000 cycles to 70–80% end-of-life capacity. At one full cycle per day that is roughly 16–27 years of useful life, though most commercial duty cycles run closer to 1.2–1.5 cycles per day. We model degradation explicitly in the 25-year cashflow.

Question 11

Is battery storage safe on an occupied commercial site?

Accepted Answer

Yes when designed and installed to current standards. We specify LFP chemistry (significantly more thermally stable than NMC), exterior or fire-rated enclosure, integrated BMS, gas detection, deluge or aerosol suppression where appropriate, and we engage the local fire service early. All BESS work is delivered under our ISO 45001 safety management system with full DSEAR and HSE consideration.

Question 12

Can a battery keep my site running during a power cut?

Accepted Answer

Only if it has been specified to do so. A grid-tied BESS for self-consumption disconnects during a grid outage by design (G99 anti-islanding). True backup or island-mode operation needs additional switchgear, a microgrid controller and clear scoping of which loads stay live. We size and price this as a distinct option.

Question 13

How many EV chargers does my site need?

Accepted Answer

It depends on dwell time, vehicle type and how the chargers will be used. A car park with 8-hour dwell can support far more vehicles per socket than a customer car park with 1-hour dwell. For fleets we model the full daily duty cycle (route, return-to-base time, available grid capacity) and recommend a mix of 7 kW AC, 22 kW AC and 50–150 kW DC accordingly.

Question 14

What's the difference between AC, DC and ultra-rapid charging?

Accepted Answer

AC chargers (typically 7–22 kW) rely on the vehicle's onboard charger and suit overnight or workplace charging. DC chargers (50–150 kW) bypass the onboard charger and suit fleet turn-around and customer top-ups. Ultra-rapid (150–350 kW) targets through-route stops and HGV applications, and almost always requires a new or upgraded DNO connection.

Question 15

Will EV charging blow my grid capacity?

Accepted Answer

Often yes, if installed without modelling. Adding 6 × 22 kW chargers can add 132 kW of peak load — enough to breach the MIC on most mid-sized sites. We use half-hourly data plus load management (dynamic load balancing, scheduled charging, solar/battery integration) to defer or eliminate the need for a costly DNO upgrade.

Question 16

Can EV chargers generate revenue?

Accepted Answer

Yes. Public-access chargers (hotels, retail, leisure, golf clubs, gyms) typically run on a tariff that covers operating cost plus margin, with revenue-share arrangements available with several charge-point operators. Workplace and fleet chargers do not generate revenue directly but materially reduce fuel and BiK costs.

Question 17

What is the difference between CAPEX, PPA and EaaS?

Accepted Answer

CAPEX means you buy and own the asset — you carry the cost and keep all the savings, and the asset sits on your balance sheet. A PPA (Power Purchase Agreement) means a third party owns the asset and you pay only for the kWh generated on site, at a discount to grid. EaaS (Energy-as-a-Service) bundles generation, storage, EV, monitoring and O&M into a single fixed unit rate over 15–25 years — no CAPEX, predictable budget, single point of accountability. We model all three side-by-side before recommending one.

Question 18

Which funding route gives the best return?

Accepted Answer

Pure NPV terms, CAPEX usually wins because you retain all the savings. But it ties up capital, sits on the balance sheet and carries technical and performance risk. PPA and EaaS trade some of that NPV for zero CAPEX, off-balance-sheet treatment under most accounting standards, and risk transfer to the funder. The right answer is rarely just about IRR — it is about capital priorities, tax position and risk appetite.

Question 19

Is there public-sector funding available?

Accepted Answer

Yes. The Public Sector Decarbonisation Scheme (PSDS), Salix loans, and various devolved schemes (Ynni Cymru in Wales, Scotland's Heat Network Fund, etc.) provide grants and concessional loans for public-sector decarbonisation. Eligibility, timing and matched-funding rules change frequently. We help structure compliant applications and have delivered projects through PSDS, Salix and Ynni Cymru.

Question 20

Can a PPA or EaaS be cancelled if I sell the site?

Accepted Answer

Yes — most agreements include a clear novation route to a new occupier or owner, plus a contractual buy-out schedule. We always negotiate this up-front so the contract is not a barrier to a future sale or restructure.

Question 21

How does the Smart Export Guarantee (SEG) work?

Accepted Answer

SEG obliges licensed electricity suppliers (those with > 150,000 customers) to offer a tariff for exported renewable generation up to 5 MW. Rates vary widely (typically 4–15p/kWh) and contract terms differ — fixed, variable, or wholesale-linked. For commercial sites the SEG income is a useful uplift but rarely the primary economic driver; self-consumption value is usually 3–6× higher.

Question 22

Do I need a G99 application?

Accepted Answer

Anything above 16 A per phase (roughly 3.68 kW single-phase or 11 kW three-phase) requires a G99 connection application to your Distribution Network Operator (DNO) — Western Power Distribution / National Grid Electricity Distribution, UK Power Networks, SSEN, Northern Powergrid, etc. Below that threshold a G98 notification is sufficient. We handle pre-application, full submission and offer negotiation as standard.

Question 23

What is the difference between G99 and G100?

Accepted Answer

G99 governs the connection itself — protection settings, fault levels, anti-islanding. G100 governs export limitation: how a site is allowed to electrically guarantee it will not export beyond an agreed limit, using an export-limitation scheme certified to ENA EREC G100. Most commercial sites that want to install more solar than their headroom allows do so via a G100 scheme.

Question 24

What if my DNO connection offer is unaffordable?

Accepted Answer

Expensive offers usually come from required reinforcement upstream of the site. Three levers typically unlock a viable offer: (1) accepting export limitation under G100 so the DNO does not need to reinforce for export, (2) accepting Active Network Management (ANM) so output is curtailed during constraint, or (3) revising system sizing or phasing. We negotiate this as standard and have unblocked several offers that originally came back at 7-figure reinforcement costs.

Question 25

How long does a DNO connection take?

Accepted Answer

G98 is effectively instant (notification only). A G99 ≤ 50 kW connection is usually offered within 45 working days. Larger or constrained connections can take 3–9 months from application to energisation, and grid-constrained areas (parts of the South West, East Anglia, and South Wales) can be longer. We start the DNO conversation in parallel with design so the critical path is not the connection.

Question 26

What's the difference between MIC and AIC?

Accepted Answer

Maximum Import Capacity (MIC) is the kVA your site is contractually allowed to draw from the grid; Available Incoming Capacity (AIC) is what the network can physically deliver. New EV or process loads usually push against MIC first. A capacity review often shows headroom is available without a full upgrade — saving 6–18 months and significant connection cost.

Question 27

What does an O&M contract actually cover?

Accepted Answer

A credible commercial O&M scope covers remote 24/7 monitoring, performance reporting against PR (performance ratio), proactive inverter and string diagnostics, annual physical inspections, electrical testing, cleaning where appropriate, warranty management with the OEM, and a response-time SLA for site visits. We benchmark performance monthly and report it back to finance as £ lost, not just kWh missed.

Question 28

How often should commercial solar panels be cleaned?

Accepted Answer

Most UK commercial roofs do not need cleaning more than once every 2–3 years — natural rainfall handles the rest. Sites near agriculture, heavy industry, food processing or major roads can lose 4–8% annual yield without cleaning and may justify an annual clean. We monitor soiling losses and only recommend a clean when the £ recovered exceeds the cost.

Question 29

What happens if an inverter fails?

Accepted Answer

Inverters are the most active component in a PV system and the most common failure point at year 10–15. Under our O&M, we detect a failure within minutes through remote monitoring, raise the warranty claim with the OEM, and either deploy a hot-swap unit or replace under warranty. Downtime is typically measured in days, not weeks.

Question 30

What accreditations should a commercial installer hold?

Accepted Answer

For UK commercial work look for: MCS (for systems where SEG is claimed), NICEIC or NAPIT (electrical), CHAS or SafeContractor (H&S), ISO 9001 (quality), ISO 14001 (environment) and ISO 45001 (H&S management). Nuvolt holds all of the above and aligns design with IET BS 7671, BS EN 62446 for PV commissioning, and the BRE solar PV roofs guidance.

Question 31

Are you CDM-compliant?

Accepted Answer

Yes. Every project is delivered under the Construction (Design and Management) Regulations 2015 with a named Principal Designer and Principal Contractor where applicable, a project-specific construction phase plan, and full pre-construction information shared with the client. CDM compliance is non-negotiable for any commercial install.

Question 32

How is fire risk handled on rooftop PV?

Accepted Answer

We design to the BRE / RC62 guidance on rooftop solar fire safety: appropriate DC isolation, rapid-shutdown where required, cable management away from combustibles, and clear access pathways for fire and rescue. For sites with insurance scrutiny (food, logistics, heritage) we engage the insurer's risk engineer at design stage.

Question 33

Does on-site solar reduce my Scope 2 emissions?

Accepted Answer

Yes — on-site generation that you self-consume directly reduces your Scope 2 (purchased electricity) emissions under the GHG Protocol, using the location-based or market-based method. Exported generation does not reduce your own Scope 2 but can support REGO-backed claims if appropriately certified. We provide audit-ready generation data for SECR, ESOS, CDP and SBTi reporting.

Question 34

What is SECR and does it apply to me?

Accepted Answer

Streamlined Energy and Carbon Reporting (SECR) applies to large UK companies and LLPs (typically > 250 staff, > £36m turnover or > £18m balance sheet) and to all quoted companies. It requires annual disclosure of UK energy use, associated emissions and at least one efficiency action. On-site solar and battery deployments are exactly the kind of action SECR was designed to surface.

Question 35

How does solar interact with ESOS?

Accepted Answer

ESOS Phase 3 requires qualifying large UK organisations to identify cost-effective energy-saving opportunities every four years and, from Phase 3 onward, to publish an action plan and report progress. Half-hourly data audits, solar feasibility and battery business cases are explicitly the type of measure ESOS auditors look for.

Question 36

Will buying RECs / REGOs replace the need for on-site renewables?

Accepted Answer

Not really. REGOs (Renewable Energy Guarantees of Origin) and equivalent RECs allow market-based zero-Scope-2 claims, but increasingly investors, customers and the SBTi expect demonstrable additionality — i.e. actually adding new renewable capacity. On-site PV is the clearest form of additionality available to most commercial buyers.

Question 37

What size projects does Nuvolt deliver?

Accepted Answer

We are sized for commercial and industrial work — typically 50 kWp to 5 MWp on rooftops and ground-mount, plus integrated battery and EV packages of equivalent scale. We do not do domestic single-dwelling work; the engineering, compliance and commercial frame is materially different.

Question 38

Do you self-deliver or sub-contract?

Accepted Answer

We self-deliver design, engineering, commissioning and O&M with our in-house team, and we use long-standing pre-qualified specialist sub-contractors for civils and specific trades. Every project has one named Nuvolt project manager who owns the client relationship end-to-end.

Question 39

How long does a typical engagement take from first call to energisation?

Accepted Answer

For a standard 250–500 kWp rooftop with a clean DNO position, expect 12–20 weeks: 2–4 weeks feasibility and HH data audit, 4–8 weeks DNO and design, 6–10 weeks delivery and commissioning. Funded routes (PPA/EaaS) and constrained grid positions can extend the front-end by 4–8 weeks.

Question 40

Where do you operate?

Accepted Answer

Nuvolt is headquartered in South Wales and delivers commercial energy infrastructure across England, Wales and Scotland. The bulk of our work is England & Wales but we have delivered projects from Cornwall to the central belt of Scotland.

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