Solar pumping is one of the few renewable applications where the storage problem disappears, because water in a tank is the storage and it is far cheaper than a battery. This project drives a DC or BLDC pump directly from a panel through an MPPT stage, with no battery in the system at all, sizes the array from the daily water requirement and the total head rather than from the pump's nameplate, and protects the pump against the two things that kill it: running dry, and starting repeatedly under weak irradiance.
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 9,870 to Rs 22,980 |
Spares and replacements 15 % — you will destroy something | Rs 1,481 to Rs 3,447 |
Consumables and hardware Wire, connectors, headers, screws, heatshrink | Rs 1,184 to Rs 2,758 |
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 13,085 to Rs 30,785 |
| Each, split 3 ways | Rs 4,362 to Rs 10,262 |
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 3.9 week figure assumes 9 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 array feeds an MPPT stage that keeps the panel at its maximum power point rather than letting the pump load pull it down, so the pump starts earlier in the morning and runs later into the evening.
Flow is estimated from pump speed or measured with an inline flow sensor, and integrated to give the day's delivered volume.
Running dry changes the load on the pump: with no water to move, the current falls noticeably. The controller detects that signature and stops the pump before the seal overheats.
Under weak irradiance the pump would start, stall the array, restart and stall again. A minimum-power threshold with hysteresis stops that cycling, which is what destroys pump motors in cheap installations.
The tank level sensor stops the pump when the tank is full, and the check valve stops the column of water in the delivery pipe running back through the pump when it stops.
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.
P = rho x g x Q x H
1000 x 9.81 x 0.001 x 5 = 49 W. This is the power that actually lifts water; everything else in the system is loss.
P input = hydraulic power / (pump efficiency x motor efficiency)
49 / 0.45 = 109 W. Small DC pumps are not efficient machines, and using the nameplate wattage instead of working from head and flow is the most common sizing error in this project.
Q = P x efficiency / (rho x g x H)
100 x 0.45 / (1000 x 9.81 x 5) = 9.17e-4 cubic metres per second, which is 0.92 litres per second. Double the head and the flow halves for the same power — head, not power, is what governs a pumping system.
Total head = static lift + delivery height + friction losses
Friction loss rises with the square of velocity, so an undersized delivery pipe quietly eats the array. Sizing the pipe generously is far cheaper than adding panels.
Array W = daily energy / (peak sun hours x derating)
600 Wh required, 5 peak sun hours, 0.75 derating for temperature, dust and converter loss: 600 / (5 x 0.75) = 160 W. Round up to the next standard panel size.
| Item | Qty | Unit cost |
|---|---|---|
Solar panels Two 100 W, 12 V panels in series or parallel to suit the pump | 2 | Rs 2,600 to Rs 4,500 |
DC pump 12 or 24 V DC submersible or surface pump, 5 m head class | 1 | Rs 1,200 to Rs 4,000 |
MPPT converter Pump-rated MPPT module, or the controller from the MPPT project | 1 | Rs 900 to Rs 2,800 |
Flow sensor YF-S201 hall effect inline flow sensor | 1 | Rs 180 to Rs 450 |
Level sensor Float switch, or an HC-SR04 mounted above the tank | 1 | Rs 90 to Rs 350 |
Current sensor ACS712 30 A on the pump feed | 1 | Rs 150 to Rs 380 |
Microcontroller board Arduino Nano or ESP32 | 1 | Rs 250 to Rs 700 |
Check valve and fittings Non-return valve, elbows, unions, 25 mm pipe | 1 | Rs 400 to Rs 1,100 |
Mounting frame Panel mounting structure and pump stand | 1 | Rs 800 to Rs 2,400 |
Display and enclosure 16x2 LCD, weatherproof ABS box, glands | 1 | Rs 350 to Rs 900 |
Cabling MC4 connectors, 4 sq mm cable, fuse and isolator | 1 | Rs 350 to Rs 900 |
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 13,085 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. A final year report is normally 60 to 90 pages with a substantial literature survey, and many departments expect a paper submission alongside it.
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.
Because the water tank is the storage. A battery is the most expensive and shortest-lived component in a small solar system, and pumping is one of the rare loads that does not need power at a fixed time — it only needs to move a certain volume in a day. Storing energy as potential energy in an elevated tank costs almost nothing and lasts as long as the tank does.
Total head is the sum of the static lift, the delivery height and the friction losses in the pipework, expressed as a height of water. Hydraulic power is proportional to the product of flow and head, so at fixed input power the flow you get is inversely proportional to the head. A pump that delivers plenty at three metres may deliver almost nothing at fifteen.
By watching the motor current. Moving water is the pump's load, so with no water the hydraulic load disappears and the current falls below its normal running band. A sustained low-current reading while the pump is commanded to run is the dry-run signature, and the controller stops the pump before the seal, which is water lubricated, overheats.
Because near the starting threshold the pump's inrush pulls the array voltage down, the pump stalls, the array recovers and the cycle repeats. Each of those starts is a large current pulse through the motor. A threshold with hysteresis means the pump only starts when there is enough power to keep running, and only stops well below that point.
Without it, the column of water standing in the delivery pipe runs back down through the pump every time it stops. That spins the impeller backwards, wastes the energy already spent lifting that water, and means the pump has to refill the pipe on every restart before it delivers anything.
Normally taken as a Diploma project (C-20, 6th sem) or B.E. mini project (5th/6th sem) or B.E. final year project (7th/8th 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.