A fixed solar panel is only pointed correctly at the sun for a few minutes a day. A tracker keeps the panel normal to the incoming light, and the gain is real but smaller than most reports claim once the tracker's own consumption and its mechanical losses are counted. This project uses four light-dependent resistors in a shaded quadrant to sense which way the sun has moved, drives two axes to null that difference, and logs the output of the tracked panel against an identical fixed panel side by side, so the results chapter contains a measured gain rather than a quoted one.
Not just the parts. Teams budget from a component list, then run out in week six on wire, connectors and the driver board they destroyed. These are the lines that catch them.
| Line | Cost |
|---|---|
Components and materials From the bill of materials | Rs 4,772 to Rs 11,830 |
Spares and replacements 15 % — you will destroy something | Rs 716 to Rs 1,775 |
Consumables and hardware Wire, connectors, headers, screws, heatshrink | Rs 573 to Rs 1,420 |
Perfboard and assembly | Rs 150 to Rs 400 |
Report, printing and binding Two or three bound copies, plots and the plagiarism check | Rs 400 to Rs 1,200 |
| Total | Rs 6,611 to Rs 16,625 |
| Each, split 3 ways | Rs 2,204 to Rs 5,542 |
Indicative bands last checked in August 2026 — a guide, not a quotation. Prices move and vary by seller, and anything you can borrow from the lab comes straight off the total. The 3 week figure assumes 7 person-weeks of work shared between 3; students past 4 add coordination rather than output, so the estimate stops improving there.
The same chain in words
The four LDRs sit in a cross with a raised divider between them, so any misalignment with the sun shades some quadrants more than others.
The controller reads all four, forms the east minus west difference and the north minus south difference, and drives each axis to bring its difference toward zero.
A dead band around zero stops the drives hunting: without it the tracker chatters continuously and consumes more than it gains.
Limit switches at both ends of each axis stop the mechanism driving into its own frame, which is the failure that destroys most student trackers on the first cloudy day.
Both panels are loaded with identical resistors and their voltage and current logged at the same instants, so the comparison is like for like.
This is the chapter that separates an engineering project from an assembly job. Every value below carries the formula that produced it and the assumptions it rests on — check them against your own ratings before you use them, because your motor is not this motor.
T = m x g x d, with d the offset of the centre of gravity from the axis
A 1.8 kg panel with its centre of gravity 20 mm off the pivot: 1.8 x 9.81 x 0.02 = 0.35 N.m. Balancing the panel about its axis is what keeps this term small, and it costs nothing to do.
q = 0.5 x rho x v^2, then F = q x A and T = F x lever arm
At 10 m/s, q = 0.5 x 1.225 x 100 = 61.25 Pa. A 480 x 350 mm panel is 0.168 sq m, so F = 10.3 N. This is three times the gravity term and it is why the next line matters.
Compare the worst-case torque with the drive's holding torque
The servo comfortably handles the 3.6 kg.cm gravity term but not the 10.5 kg.cm wind term, and a servo holds position by drawing current against the load. A worm gearbox is self-locking, so wind torque is taken by the gear teeth and not by the motor — that is the honest answer for any tracker meant to live outside.
Energy per move x moves per day, compared with the day's generation
Two servos drawing 0.5 A at 6 V for one second, sixty times a day, is 360 J or 0.1 Wh. Negligible — but only if the drives are de-energised between moves. A servo left holding against wind load can draw more than the tracking gain, which is the single most important measurement in this project.
Set wider than the sensor noise, narrower than the useful pointing error
Cosine loss is gentle near the optimum: being ten degrees off costs only about 1.5 percent of the available power, since cos(10 deg) = 0.985. There is no benefit in chasing the last degree, and a great deal of wear in trying.
| Item | Qty | Unit cost |
|---|---|---|
Solar panels 20 W, 12 V polycrystalline, two identical units | 2 | Rs 700 to Rs 1,600 |
Microcontroller board Arduino Uno or Nano | 1 | Rs 250 to Rs 500 |
LDRs 5 mm GL5528 with 10 kOhm dividers | 4 | Rs 8 to Rs 25 |
Servo motors MG996R metal gear, 11 kg.cm, or a worm-geared DC motor | 2 | Rs 300 to Rs 700 |
Motor driver L298N or BTS7960, only if using DC gear motors | 1 | Rs 150 to Rs 450 |
Limit switches Micro lever switches, two per axis | 4 | Rs 15 to Rs 45 |
Current and voltage sensors INA219 modules, one per panel | 2 | Rs 180 to Rs 400 |
Data logging SD card module or ESP32 WiFi logging | 1 | Rs 120 to Rs 400 |
Mechanical frame Aluminium extrusion, bearings, fasteners, base plate | 1 | Rs 900 to Rs 2,600 |
Power supply and battery 12 V 7 Ah SLA with a small charge controller | 1 | Rs 700 to Rs 1,600 |
Wiring and connectors MC4 connectors, cable, terminal blocks | 1 | Rs 200 to Rs 600 |
Specifications are written as ratings rather than brands, so any equivalent part works. Where a line says to borrow from the lab, do — it is usually the largest number on the page, and the total drops to Rs 6,611 at the low end without them.
None of these blocks you — they are learnable inside a semester. Each one you do not have costs a couple of weeks, so count them into your plan.
Anything marked required is a blocker, not a difficulty. Arrange the access before you commit to the project, not after.
Use these when your guide says the scope is too small, or when you want something in the results chapter that nobody else in your batch will have.
The structure below is what a project report is marked against, with the mistake that costs marks in each chapter. There is no template to download and there will not be one: the writing is your work, and a site that did it for you would be helping you cheat rather than helping you pass.
A diploma report is typically 40 to 60 pages. The design and results chapters carry the marks; the literature survey can be short. A mini project report runs to about 40 to 50 pages, and the literature survey is usually brief. Guides expect one clear objective, met and measured.
The full report guide — front matter, conventions and page countsOne paragraph covering what the problem is, what you built, and what the result was. Written last, even though it appears first.
Loses marks: Describing the problem and the method but never stating a result. If there is no number in your abstract, it is not finished.
Why the problem matters, the context it sits in, and a clear statement of the objectives your project set out to meet.
Loses marks: Objectives written so vaguely that nobody can tell at the end whether they were met. Write objectives you can tick off in the conclusion.
What has already been done, what each approach achieved, and the specific gap your work addresses.
Loses marks: A list of paper summaries with no comparison and no gap. The survey exists to justify your design choice, so end it by saying what you chose and why.
The system as a whole: the block diagram, what each block does, and the signal or power path between them.
Loses marks: A block diagram copied from a datasheet or another report. Draw yours to match what you actually built, including the parts that are inconvenient.
Every component value and rating, with the formula, the assumptions and the arithmetic that produced it. This is the chapter that distinguishes an engineering project from an assembly job.
Loses marks: Component values with no justification. If a resistor is 10 kOhm, the report must say why it is not 1 kOhm.
The circuit as built, the PCB or wiring, the flowchart, and the parts of the code that carry the actual logic.
Loses marks: Twenty pages of pasted source listing. Include the flowchart and the few functions that matter, and put the full listing in an appendix.
What you measured, in tables and graphs, compared against what you predicted in the design chapter — including where they disagreed.
Loses marks: Photographs of the working model presented as results. A photograph is evidence that it exists, not evidence that it works. Results are measurements.
Whether each objective was met, what the measured performance was, and what the honest next step would be.
Loses marks: Future scope written as a wish list of unrelated features. It should follow from a limitation you actually hit.
Every source in a consistent style, plus datasheets, full code listings and the complete bill of materials.
Loses marks: Citing a blog or a video where a datasheet or a standard exists. Cite the primary source for anything you relied on.
The demonstration is half the assessment. These are the questions this project invites, and the answers are written the way you would give them out loud.
The power a panel collects depends on the cosine of the angle between the incoming light and the panel's normal. A fixed panel is only at zero angle for a moment each day, so it loses the cosine of the offset for the rest. Keeping the normal pointed at the sun holds that cosine at one throughout the day, and the biggest gains come in the early morning and late afternoon when a fixed panel is worst aligned.
Because the LDR difference never settles at exactly zero — noise, cloud edges and the sun's own movement keep it wandering. Without a dead band the drives respond to every fluctuation, so the tracker hunts continuously, wastes energy and wears out. The dead band is set wider than the sensor noise but narrow enough that the residual pointing error costs almost nothing, since cosine loss near the optimum is very small.
Usually not, commercially. Single axis tracking captures most of the available gain because the sun's daily east to west travel is far larger than its seasonal north to south drift. The second axis adds cost, another failure point and more maintenance for a small additional yield, which is why most utility scale plants use single axis horizontal trackers.
A worm drive is self-locking: the output cannot back drive the input, so wind load is carried by the gear teeth rather than by the motor. A servo holds position electrically, drawing current proportional to the load, and loses position entirely when powered down. For a mechanism that has to sit outside in wind, self-locking is the right property.
By computing the solar position from date, time and the site's latitude and longitude using solar geometry — the declination, hour angle, then altitude and azimuth. It is deterministic, works when the sun is behind cloud, and cannot be fooled by a bright reflection, which is a real failure mode of LDR sensing.
Normally taken as a Diploma project (C-20, 6th sem) or B.E. mini project (5th/6th sem) project. If yours is a different course, the extensions above scope it up and the simpler half of the design scopes it down — the arithmetic does not change. Back to all projects.