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Power & Sun

Digitising solar energy

What would solar do here?

Grid connected, hybrid with a battery, off grid, or alongside diesel generators — worked out from the measured sunlight at your own coordinates, on the roof you actually have, and valued at the rate you actually pay.

  • Real irradiance data
  • Grid, hybrid, off grid or with diesel
  • No account needed
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The full design tool is free for 60 days or 5 completed projects. No card needed.

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Three questions, one honest answer

Tell us the system, the site and what you pay. The answer is an engineering estimate from measured sunlight — energy and savings only, never a price, and nothing is stored unless you ask us to call.

1 What kind of system? This decides which of the questions below are worth asking.
2 Where it is, and what the roof is like The sunlight at your coordinates is the largest input to everything that follows.
Shape
Anything shading it?
3 What you use, and what it costs Your own tariff, so the saving is yours rather than an average.
An off-grid or hybrid system is sized against what you use, so one of these is needed. Solar beside generators is sized against the load they carry, so one of these is needed.
When do you use most of it? This decides how much of the generation you use rather than export.
Add a battery? Without one, solar can carry about 60% of the daytime load. With one, the sets rest through the day and into the evening.

Nothing is stored. No account, no email, no follow-up unless you ask.

Energy figures only — no price, and not a quote. This estimate shows what a system could generate and what that energy is worth at the tariff you give. It never prices a system: a price comes from an engineer after a site survey. The figures are estimates under our engineering disclaimer. What you enter here is not stored. If you send an enquiry, we keep your details to answer it and delete an enquiry that does not become a job after 24 months — see the privacy notice.

Your estimate appears here

Answer the three sections and press Work it out.

  • An array sized to your roof and your load
  • Generation from the real sunlight at your coordinates
  • Storage sized for backup, or for days off grid
  • What it is worth at your own tariff

What this does, and what it doesn't

What it does

  • Uses measured irradiance for the cities in the list, cached after the first look-up, and a modelled climate anywhere else. The result says which it used.
  • Puts that sunlight onto the plane your roof actually is — its tilt and the way it faces — rather than assuming an ideal south-facing slope.
  • Takes off temperature, soiling, wiring, inverter and shading losses, with a soiling allowance that is higher in dusty climates because that is where it bites.
  • Sizes the array against your roof and your consumption, and says which one ran out first.
  • Off grid, sizes on the leanest month and on the days of autonomy you asked for, and tells you plainly when the roof cannot carry the load.

What it doesn't

  • Look at your roof. Structure, obstructions, access and the switchboard all move the answer, sometimes a long way.
  • Know your load shape. It works from one question about when you use power, where a design reads your half-hourly data.
  • Price anything. Not the system, not the battery, not the work.
  • Simulate the year hour by hour. The full tool runs 8,760 steps, checks strings against the inverter, sizes cables and protection, and produces a bill of materials.
  • Replace an engineer. Every number here is indicative and carries a band of roughly plus or minus fifteen per cent.

Features

Everything from the first enquiry to the handover

The estimator on this page is the front door. Behind it is the tool our engineers use for every project: survey, design, price, issue and deliver, in one place.

Win the work

Find the customer and the opportunity, and keep in touch until it is signed.

  • Public solar estimator for on-grid, hybrid, off-grid and PV-diesel systems, on this page
  • Enquiries land in the CRM as leads, with consent recorded
  • Customers, contacts, deals and a pipeline by stage
  • Follow-ups and tasks, with email templates for offers and reminders

Survey the site

Everything the design rests on, recorded once and checked.

  • Site on the map, with roofs, ground arrays and carports drawn to size, obstructions included
  • Roof detection and measured irradiance layers from Google Solar (Enterprise)
  • Read a site from a photo or drawing with AI (Enterprise), or import a KML outline
  • Survey assessment of roof, structure, soil, grid and access, turned into design checks
  • Weather from PVGIS, NREL NSRDB, NASA POWER or Solcast, or measured monthly data
  • Consumption from bills or monthly readings, load shapes, and flat, slab or time-of-use tariffs

Design the system

An engineer's design, worked out hour by hour and checked against the equipment.

  • On-grid, hybrid with storage, off-grid, and PV-diesel hybrid with generator dispatch
  • Equipment chosen automatically from your catalogue, or picked by hand
  • String sizing, MPPT allocation, cable sizing and protection, checked at cold and hot extremes
  • Battery sizing for backup, autonomy, self-consumption and peak shaving
  • Hour-by-hour simulation over a full year, single-axis trackers and bifacial gain
  • Loss waterfall, P50 to P99 yield, and shading and soiling allowances
  • Utility-scale plant model: inverter blocks, transformers and the MV network
  • Single-line diagram with DXF export, a 3D site model, and designs compared side by side
  • Design copilot: ask Claude about a design or for a change (Enterprise)

Equipment catalogue

One list the designs, the prices and the documents all read from.

  • Modules, inverters, batteries, mounting, trackers, generators, transformers, switchgear, string boxes and cable
  • The Power & Sun range and its distributed brands, with full datasheets
  • Import from a spreadsheet or PVsyst PAN and OND files, or read a datasheet with AI (Enterprise)
  • Prices kept with where they came from, in any currency, and a check that nothing is quoted unpriced

Quote and issue

From the design to a priced, signed-off offer the customer can open.

  • Bill of quantities with the cost build-up and country tax rules
  • Payback, IRR, NPV, LCOE and a sensitivity analysis; IPP and PPA models
  • Engineering review and approval by a second engineer before anything is priced
  • Techno-commercial EPC offer and customer proposal on your letterhead, shared by link
  • Project report, slides (PDF and PowerPoint) and a document checklist
  • Every figure in the project's own currency

Deliver and review

The project after the order, and the business across all of them.

  • Delivery plan, milestones and documents
  • Task board, Gantt chart, calendar and timesheets
  • Snag list, commissioning checks and handover
  • Reports on pipeline, proposals, capacity and the team, in Excel and PDF

For your team

Run by your organisation, secured, and supported.

  • Your organisation and team, with roles for administrators, engineers and sales
  • Two-factor sign-in, and data kept to your organisation
  • Search, or ask the assistant, from any page
  • Step-by-step guide, user guide, glossary, and help with any issue
  • Monthly or annual plans, paid by card or bank transfer, with discount coupons

Start the free trial See plans and pricing

From estimate to installation

Solar for every kind of site

Homes
HomesRooftop systems sized to the roof and the bill, with a battery where the grid is unreliable.
Business and industry
Business and industryFactory, warehouse and commercial roofs, with storage to cut peak demand and keep production running.
Utility and ground-mount
Utility and ground-mountGround-mounted plants and storage, engineered, procured and built under one EPC contract.
Two engineers checking a solar plant

Engineered by Power & Sun

A design an engineer signs, and the equipment to build it

When you are ready, our engineers turn this estimate into a full design: an hour-by-hour simulation, strings and cables checked against the equipment, a bill of quantities and a firm EPC offer.

  • Site survey, structural and grid checks
  • Tier-1 modules with our own inverters and storage
  • Commissioning, performance testing and O&M
Talk to an engineer
Mastter series
Mastter seriesHybrid inverters, single and three phase
Ultimatte series
Ultimatte seriesOn-grid and off-grid inverters
Tusk series
Tusk seriesLow and high voltage battery storage
Bison series
Bison seriesWall and floor-standing lithium batteries
Tusk C&I
Tusk C&ICommercial and industrial storage cabinets

Power & Sun is part of the Orange Overseas group

Orange Overseas
Orange OverseasParent group
pv.market
pv.marketAI digital marketplace for solar equipment

Want the real thing?

Leave your details and an engineer picks it up: a survey, a proper hour-by-hour simulation, an equipment list and a price you can hold us to.

  • A site survey, not a satellite guess
  • A full technical report stating every assumption
  • A priced bill of quantities
A family running beside a solar array

We use your details to answer your enquiry, and to carry out the work if it goes ahead. Nothing else. An enquiry that does not become a job is deleted after 24 months.