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Renewable Energy

Renewable Energy Lab consisting of Solar Cell and Solar PV Panels and Trainer. (SURYAMITRA COMPLIANT), Wind Energy Trainer and Simulation Software for Solar PV, Solar Thermal, Hybrid Solar PVT and Geothermal Systems.



List of experiments (Solar cell experiment setup):

  1. Study of I-V Characteristics of Solar cell.

  2. Study of series combination of solar cells.

  3. Study of parallel combination of solar cells.

  4. Study of dependency of solar cell I-V characteristics on light intensity.

  5. Study of dependency of solar cell I-V characteristics on temperature.

  6. Study of shading effect on solar cell parameters.

  7. Study of Photovoltaic effect in ubiquitous semiconductor PN junction (diode).

  8. Study of 6Vbattery charging using solar cell

  9. Study of 6Vbattery discharging using DC fan & LED lamp


List of experiments (Spectral Response & Carrier Lifetime Measurement setup):

  1. Measurement of Carrier Lifetime for a solar cell.

  2. Measurement of Spectral Response for a solar cell.


List of experiments (SPV / MAIN RACK - Covers NISE/ DGET course curriculum):

  1. To demonstrate the I-V & P-V module with varying radiation and temperature level

  2. To demonstrate the I-V & P-V characteristics of series combination of PV module

  3. To demonstrate the I-V & P-V characteristics of parallel combination of PV module

  4. To show the effect of variation in tilt angle on module power

  5. To demonstrate effect of shading on module output power

  6. To demonstrate the working of diode as blocking diode

  7. To draw charging and discharging characteristics of battery

  8. Observe the O/P waveform of inverter in auto mode

  9. Workout power flow calculations of standalone PV system AC load with battery

  10. Workout power flow calculation of standalone PV system DC load with battery

  11. Find MPP by varying the resistive load across the PV panel

  12. To study effect of shading on the O/P of solar panel

  13. To do shading analysis on the site where solar PV systems to be setup

  14. To study battery characteristics

  15. To understand difference between MPPT & PWM charge controllers, efficiency of MPPT & PWM charge controller & energy flow in a system involving MPPT& PWM charge controller

  16. To understand and determine the DC flow in a solar system

  17. To understand how a solar PV standalone system works

  18. To determine power flow in a solar system

  19. To convert normal inverter to a solar inverter system

  20. To compare the performance of two inverters using electro-scope (Optional)


List of experiments (PC Based IV/PV Characteristics Plotting):

  1. To perform experiment to study & plot IV/PV characteristics of SPV module on PC screen using VWB V11.x software, using MPPT controller & graph window.

  2. To perform experiment to study & plot IV/PV characteristics of SPV module on PC screen using VWB V11.x software, using data logger with its scientific calculator & graph window.

  3. To perform experiment to study MPPT charge controller in VWB software with following algorithms/ schemes

           a.    Incremental Conductance (Inc Cond)

           b.    Perturb & Observe (P & O)

           c.     75% of Voc




List of experiments

  1. To study characteristics of wind velocity and generator power.

  2. To analyze effect of pitching (blade angles) on performance of wind turbine.

  3. To study yawing due to change in direction of wind.

  4. To perform experiment to study working of inverter and calculate its efficiency.

  5. To study VI characteristics of wind turbine.

  6. To study working of MPPT charge controller.

  7. To study working of DC application (load).

Future Scope:

The above systems can be GRID TIED to a Transmission Line Double Bus Bar Trainer, with additional sources of Power such as Generator and Main Line. This can be further expanded to a Generation – Transmission – Distribution system, to a level of a complete MICRO / SMART Grid Solution with SCADA Automation.




Polysun is a software that enables users to effectively simulate solar-thermal, photovoltaic and geothermal systems.

With the Polysun software from Vela Solaris you can rely on a multi-practice simulation of your energy system with reliable results in terms of functionality, energy efficiency and profitability – from single-family homes to districts, worldwide and for all market-standard technologies.


Polysun is the only commercial simulation software for renewable energy systems which allows you to combine different technologies with each other (solar thermal, PVT, photovoltaics, heat pumps, ground-source loops, cogeneration units etc.) and the only software which allows you to edit the system templates and to create your own ones. This is the most important selling point. Compared to other academic software, thanks to its clear depiction of the systems and its modularity it is much easier to use and therefore particularly suitable for teaching. Students can learn quickly how to use it and get a good overview of the market thanks to the rich databases.



Polysun Designer depicts your energy system at an early planning stage. Systems can be built up quickly and potential for optimization revealed. This gives you planning security and convinces your customers with sophisticated and economical energy concepts. Polysun Designer intelligently combines applications to meet heating, cooling, electricity, and electromobility requirements. 


Using simple drag-and-drop you can choose from 150,000 system components that are always up-to-date and simulate the interaction of the energy system in dynamic time steps up to a resolution of steps in seconds. You can define intelligent control logic in a completely flexible manner, thereby additionally increasing the energy and cost efficiency of your solution.

  • Free and easy programming of control logics
  • More than 150,000 deposited energy system components
  • 1,000 practice-tested templates for energy system concepts
  • Simulation of every market-standard technology – worldwide
  • Energetic monthly and annual balance sheets
  • Technical result reports and profitability calculation

1000’s of Readymade Templates for Solar Photovoltaics and Thermal


Compare Scenario Results


Sun and Shading data from Maps or Database


  • Validated calculation models for solar thermal collectors, thermal tanks (water, ice and ground tanks), ground-source loops, conventional heat generators, biomass boilers, air-to-water, brine-to-water and water-to-water heat pumps, adsorption and absorption chillers, hybrid collectors (PVT), photovoltaic modules, inverters, batteries, cogeneration units, fuel cells and many more

  • Hydraulic interconnections can be arranged at will

  • Controlling strategies for the hydraulic systems can be freely defined

  • Comprehensive product data bases of heat pumps, photovoltaic modules, inverters, batteries, solar collectors, cogeneration units and many more components

  • Catalogs stored in the Cloud, no need to update your data bases

  • Includes a selection of more than 1,000 pre-configured hydraulic templates (including company templates)

  • Hydraulic templates for large-scale thermal systems, local, district heating and energy networks

  • Import of thermal loads for process heat applications on an hourly or 15-minute-basis

  • Integrated building model to calculate heating and cooling loads

  • Interfaces to import the heating energy demand according to the German EnEV, the Swiss SIA etc.

  • Automatic variation of parameters

  • Reports that are accepted for diverse applications for subsidies

  • Easy comparison of simulation results of several system diagrams

  • Detailed evaluation of simulation results per time step, 15 min., hourly or monthly values

  • Real time visualization using simulation analysis and graphic display of results

  • Updated Meteonorm weather data delivered through a web service (worldwide)

  • Comprehensive economic calculations including system comparison

  • Coupling of thermal and electrical systems (Power to Heat)

  • Calculation of own consumption based on entries of electric consumption profiles that are accurate down to one-minute-/five-minute-/fifteen-minute-time steps or hourly values

  • Variable prices for energy from the grid and for feed-in-tariffs can be imported

  • Off-grid systems and simulation of uninterrupted power supply systems

  • Electromobility

  • Easy to use, simple to handle



Wizards with Intelligent Filters


Horizon, Location, Obstruction Shading from Map or Database


Battery Definition


Grid Detailing


Detailed definition of Photovoltaics


Heat Pump detailing


Detailed definition of Collectors


Water Tanks


Buildings Data    


Exhaustive Manufacturers Database


Exhaustive Manufacturers Catalogs


Thermal and Electrical Results


Results Overview


Component Results


Graphical Evaluations

System Comparison Results


Graphical Evaluations


Energy Flow Diagrams


Quick and detailed Financial Analysis

Structural Obstruction and Shading data


Profitability Calculations and Comparisons


Step Simulation


Professional PDF Reports


  • As a teacher, you want to equip students for practical work and enable them to develop digitally energy systems with a future. As a recognized and globally widely used simulation tool, Polysun is ideally suited for this purpose. A comprehensive database of market-standard components and tested energy system templates make it easy for students to get started – from the first simple exercises to challenging research questions. The effective design and sizing of energy systems for buildings and districts is tested and researched with Polysun. Knowledge is acquired and internalized in a playful way. 

  • Practical teaching of content for digital energy system simulation

  • Vela Solaris was founded as a spin-off of the renowned University of Applied Sciences in Rapperswil (Switzerland) and still has strong roots in science and research today.

  • Universities value our high level of expertise and the uncomplicated support we provide to lecturers and students in the use of Polysun and in the craft of energy system simulation.

  • By collaborating on real university research projects, Polysun always keeps its finger on the pulse of the latest innovations from the research departments. At the same time, Vela Solaris, as a partner, bridges the gap between research and the market: the latest energy components are always available to researchers in the Polysun library, enabling them to investigate innovative energy concepts.

  • Students are already learning how to use simulation software used by renowned companies in their target market. In this way they are optimally prepared for later career entry.


  Make lively, hands-on lessons easier

  • Easily create exercises for students

  • Practice sessions can be easily created in Polysun and results can be exchanged between teachers and students. We provide teachers with a wide range of practice examples, which we create using our many years of practical experience. With the purchase of our software this service is free of charge.


  Training modules from our experts for students

  • The craft of digital energy system simulation – we at Vela Solaris have been experts in this field for decades. We are happy to impart this knowledge based on our Polysun software, from the introductory course to in-depth module. Vela Solaris accompanies students closely, uncomplicatedly, and flexibly in the form of webinars or on-site training. With Vela Solaris as a partner, the transfer of practical experience is effortless.



  • The most important thing when planning an energy system is that it works in practice and meets the requirements cost-effectively. This is a challenge, especially in view of the increasing regulatory requirements and sudden leaps in technology. This is where Polysun’s great strength lies: the powerful computing core of our software maps your energy system realistically at an early planning stage, giving you planning security that wins over your customers – worldwide, for all market – standard technologies and across the sector boundaries between heating, cooling and electricity.

  • With Polysun, you can effortlessly run through your various planning ideas: based on characteristic curves from real test series, you simulate more than 150,000 components, the interaction of which you can test, compare and significantly optimize their interaction with just a few clicks on their energy efficiency and profitability over any length of time. 

  • In short: Polysun offers you maximum flexibility in the representation of innovative energy systems. From ice storage to heating networks. 



  • A great deal of expertise is required for successful consulting and the sale of energy components and systems. You want to convince customers with clear decision-making bases: What energy and economic added value does a particular component provide when integrated into an overall system? What overall solution can you recommend to customers?

  • With our Polysun software you can demonstrate the advantages of your solution using tried-and-tested simulation results. We support you with templates of working complete systems to meet the electricity, heating, and cooling requirements – exactly for your applications. With just a few clicks, you can tailor the templates to your respective project and integrate your own components. As an innovative solution provider, you convince your customers with clear decision-making bases and meaningful results reports for your offers.

  • Building and district planners worldwide use Polysun as a design tool. With your components in the Polysun database, you will be visible to your customers – for an even greater sales success. Find out more. Do you want to digitalize your sales activities and generate more leads for your products and systems at a reasonable price? Integrate Polysun into your website application and run your power system simulations in the cloud.


  • As an energy service provider, you position yourself as a competent partner for energy systems with a future for smart and integral energy solutions.

  • Especially in the early planning phase, it is important to highlight ground-breaking energy solutions and all-round carefree solutions such as energy contracting. In the case of energy systems already installed, the question arises as to how energy costs can be reduced. In all these tasks, energy service providers supply valuable consulting and other services. We support you in identifying the best possible solution with precise and field-tested energy system simulations – from planning to operation. In the simulations calculated by Polysun the heating, cooling and electricity sectors grow together efficiently and intelligently, opening up new opportunities for your business. 


Vela Solaris accelerates the development of efficient energy concepts. With our Polysun software and services we enable digital simulation of energy systems, thus enabling targeted optimization of projects.
The Polysun software was developed in 1992 by the renowned Institute for Solar Technology (SPF) at the University of Applied Sciences in Rapperswil (Switzerland). Vela Solaris was founded as a spin-off in 2006. Since then we have continuously refined the simulation of energy systems and expanded it to include new energy production technologies.
We take care of our customers’ concerns with passion and great expertise. Today, more than 1,000 recognized engineering companies, manufacturers and distributors of energy system components, energy service providers and universities rely on our software solutions and services worldwide.
Our daily work is characterized by the pursuit of a better solution, close communication with our customers and the commitment to accelerate the development of efficient, holistic energy systems.

POLYSUN BIM (Add - on to Designer)

The goal of BIM projects is to significantly reduce investment and operating costs and to detect a performance gap, i.e. a deviation between planned and actual values, as early as possible. This is the only way to take cost-effective measures to prevent planning errors. Especially when planning and designing energy systems, it is important to react to changed requirements in frequent iterations and to exploit optimization potential.

In BIM projects, therefore, the focus is on collaborative work in teams and simple data exchange. The Polysun BIM add-on enables the seamless use of Polysun software in BIM projects. Data exchange via Excel, Revit and IFC is supported automatically.


Meteodata, heating load data and simulation results are thus always available to the project team at the desired location. In addition, plan specifications from the BIM project for the energy system can be conveniently stored in Polysun and their achievement evaluated at the push of a button. As a result, time is only required for planning if deviations from the plan occur – the planning time of energy systems is significantly reduced. At the same time, the risk of incorrect design of the energy system is minimized.

All simulation results remain transparently documented with Polysun-BIM and deliver added value right up to the operating phase – for easy quality assurance.

  • Minimize performance gaps and reduce investment and operating costs

  • Minimisation of planning errors through continuous digital data exchange across application boundaries

  • High planning reliability within clearly defined planning specifications

  • Significant time savings for planning reviews through automated work steps

  • Access to projects according to BIM standard

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