Guides · Faisalabad, Lahore, Punjab
Why In-House Engineering and AutoCAD Design Matter in Solar System Design
Short answer
Solar system design decides how much a system generates, how safely it runs and how well it ages, long before any equipment arrives. When the design is done in-house by engineers who also answer for the installation, the drawing, the quotation and the finished roof match each other. At Solar Works Pakistan, engineering and design are done in-house, with dedicated salaried AutoCAD experts, and our own teams build what they draw.
This guide explains what "design" actually involves, what can go wrong when it is skipped or outsourced, and what you should expect to see from any installer before you pay an advance.
What solar system design actually covers
Many buyers think of design as "choosing a kW size". Size is only the first answer. A complete design works through a chain of decisions, and each one depends on the last.
| Design step | The question it answers | What goes wrong without it |
|---|---|---|
| Load analysis | How much power you use, when, and on which loads | A system sized to one month's bill, too big or too small for the rest of the year |
| Feasibility | Whether the site, roof, connection and budget support the plan | Surprises after the advance is paid |
| Array layout | Where every panel goes, row spacing, walkways, shade | Panels placed in the shadow of tanks or stair rooms |
| String design | How panels are wired into strings and to which inverter inputs | Voltage outside the inverter's window, mismatched strings |
| Equipment selection | Which inverter, battery and protection suit this load and site | A "standard package" that fits nobody exactly |
| Structure design | Frame type, sections, anchoring and bracing for this roof | A frame copied from another job |
| Cable and protection design | Cable sizes, routes, breakers, isolators, surge protection, earthing | Hot cables, nuisance trips, missing protection |
| BOQ | A line-by-line list of everything above | A quote that cannot be checked on delivery |
Our guide to sizing under net billing explains why load analysis now matters more than ever: under the current rules, the value of solar comes mainly from using it yourself, so a design built around your real daytime use is worth more than one built around a headline kW figure.
In-house design steps
Survey
Roof, load and connection
Design
Layout, strings and protection
BOQ
Every item named
Why AutoCAD layouts matter on Punjab roofs
Punjab rooftops are rarely empty rectangles. Water tanks, stair rooms, parapets, neighbouring buildings, satellite dishes and future floors all compete for space. A scaled drawing lets the engineer:
- Fit the panels you are actually buying. Today's large-format panels are much bigger than older ones; see our solar plate size guide. A layout drawn to the real panel dimensions shows exactly how many fit.
- Check shade before it costs you output. Tanks and walls cast long shadows in winter. Our guide to shading from tanks and buildings shows why one shaded panel can pull down a whole string.
- Plan row spacing, walkways and cleaning access so panels can be reached safely.
- Route cables along the shortest protected path to the inverter.
- Place the inverter, batteries and boards where heat, water and access have been considered.
For factories, a drawing is essential. Sheds, multiple roofs, cable runs of tens of metres and several distribution boards cannot be designed reliably from photographs.
String design: the part buyers never see
How panels are wired together is invisible on a finished roof, but it decides whether the inverter can use their full output. The engineer checks that each string's voltage stays inside the inverter's operating window in both cold winter mornings and hot summer afternoons, that strings on different roof faces or with different shade go to separate inputs, and that the panel-to-inverter ratio suits the site. Our guides to series vs parallel wiring and the inverter DC/AC ratio explain the basics.
Getting this wrong rarely causes a dramatic failure. It shows up as quietly lower output for years.
Why in-house matters more than the software
Software is a tool. The real benefit of in-house design is responsibility in one place.
- The designer knows the installer. When the same company designs and builds, the drawing reflects what the team can actually build on that roof, and questions on site get answered the same day.
- The quotation follows the design. A BOQ produced from the engineering, rather than from a price list, names the brand, model, quantity, capacity and warranty of each main item. Our quotation checklist shows what to look for.
- Structures are engineered, not copied. Our structures are designed in-house and fabricated and assembled by our own teams on site. Our article on how we design structures for Punjab wind and heat explains the process.
- Faults are easier to trace. When something needs attention later, our after-sales engineers work from the same design records the installation team used.
- Changes are controlled. If a site condition changes the plan, the design is updated and the BOQ follows, rather than the crew improvising.
When design is outsourced or skipped, the installer often fits a standard kit and adjusts on the roof. That is one of the main things a lower solar quote can leave out.
How design fits into our project process
Design is not a separate product. It sits inside our standard process:
- Initial discussion by phone or WhatsApp
- Collection of electricity bills and load details
- Site survey, normally free
- Load and feasibility assessment
- Engineering and system design, including AutoCAD layouts and structure design where the project needs them
- Detailed quotation and BOQ
- Advance payment
- Procurement and execution
- Installation by our own teams
- Testing and safe commissioning
- Customer training and handover
- Monitoring and after-sales support
We treat every system as a customised engineering solution, balancing generation, reliability, budget, backup needs and future expansion rather than designing around a single number.
Design for industrial and hybrid projects
For factories, the design work goes further. Engineers look at demand patterns and MDI (see what MDI means on your bill), shift timings, motor loads, generator hours, and space for future expansion. Hybrid systems that combine solar, grid, generator and battery storage need a control scheme designed with the equipment, not added afterwards; our article on hybrid systems with generators explains our approach. Before a large project, an energy audit gives the design solid data to start from.
Solar Works Pakistan was founded in 2021. Our power-generation experience goes back to the 1980s through our founder, Akram Ullah Khan, whose career includes WAPDA and Saudi Electricity Company. We have served 300+ customers, including 50+ industrial clients, from about 6 kW to megawatt scale. See industrial and commercial solar and about us.
Questions to ask any installer about design
- Who designs the system, and are they on your staff?
- Will you visit the site before giving a firm price?
- Can I see a layout showing where each panel goes?
- How are the strings arranged, and why?
- Is the structure designed for my roof, or a standard frame?
- Does the BOQ name brand, model and quantity for every main item?
- Who will I call after handover, and will they have the design records?
Get today's price or a free site survey
Send us 12 months of bills and a few roof photos, and our engineers will tell you what a properly designed system for your site looks like. For a rough starting size, try our solar calculator.
- WhatsApp or call: 0336 666 4321
- Email: info@solarworks.pk
- Head office: Main Boulevard, Sargodha Rd, Block F FDA City, Faisalabad
- Lahore branch: 2nd Floor, Jeff Heights, Gulberg, Lahore
- Hours: 9:00 AM to 6:00 PM, daily
We serve customers throughout Punjab, and site surveys are normally free. See our Faisalabad and Lahore pages, our solar installation services, or contact us.
Frequently asked questions
What does solar system design include?
It covers load analysis, feasibility, panel layout, string wiring, equipment selection, structure design, cable and protection design, and the BOQ. Each step depends on the one before, so skipping one usually causes problems later.
Why does AutoCAD design matter for a home system?
A scaled drawing shows exactly how many panels fit around tanks, stair rooms and parapets, where shade falls and how cables run. It turns a guess into a plan you can check on the roof.
Do you design systems in-house or use outside designers?
In-house. Solar Works Pakistan has dedicated salaried AutoCAD experts, and engineering and design are done by our own team. Installation is done by our own teams as well.
Can you design a system for equipment I have already bought?
Talk to us first. We can look at the equipment and the site, but the design has to start from your load and roof, and some equipment may not suit the result.
How long does the design take?
It depends on the project. A home system follows the survey quickly; factories with several roofs, hybrid controls or battery storage need more engineering time. We give a project-specific schedule rather than a fixed promise.