Related Experiment Video
Updated: Sep 24, 2025
07:18
Experimental System of Solar Adsorption Refrigeration with Concentrated Collector
Published on: October 18, 2017
14.7K
A comparative performance analysis of stand-alone, off-grid solar-powered sodium hypochlorite generators
E Chinello1, M A Modestino2, J W Schüttauf3
1School of Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL) Station 18 1015 Lausanne Switzerland enrico.chinello@epfl.ch +41 21 69 35171.
RSC Advances
|May 6, 2022
Summary
Autonomous solar-powered generators efficiently produce sodium hypochlorite (NaClO) for water disinfection. Silicon hetero-junction (SHJ) cells offer a reliable, cost-effective solution for off-grid applications.
Area of Science:
- Electrochemistry
- Renewable Energy Systems
- Water Treatment
Background:
- Sodium hypochlorite (NaClO) is a key disinfectant in water treatment, typically produced via electrochemical methods.
- Integrating photovoltaic (PV) electricity offers potential for cost reduction and stand-alone disinfection systems.
- Assessing different PV technologies is crucial for optimizing solar-powered NaClO production.
Purpose of the Study:
- To comparatively evaluate autonomous solar-powered sodium hypochlorite generators using silicon hetero-junction (SHJ) and multi-junction (MJ) PV technologies.
- To determine the solar-to-chemical conversion efficiencies (SCE) under real-world conditions.
- To analyze the economic viability and production rates for different PV configurations.
Main Methods:
- Developed and tested three solar-hypochlorite generators: 4-cell SHJ (4SHJ), 5-cell SHJ (5SHJ), and multi-junction (MJ) cells with a solar concentrator.
- Measured SCE under real atmospheric conditions.
- Utilized weather databases for year-round efficiency simulations and economic analysis.
Main Results:
- Achieved SCE of 9.8% (4SHJ), 14.2% (5SHJ), and 25.1% (MJ).
- Projected yearly NaClO production rates ranging from 7.2-28 g/cm² based on PV technology, location, and electronics.
- Demonstrated economic competitiveness compared to ultraviolet disinfection systems.
Conclusions:
- Autonomous, solar-powered sodium hypochlorite generators are feasible for off-grid water disinfection.
- SHJ solar cells present a reliable and promising technology for stand-alone solar-chemical devices.
- Solar-powered NaClO production offers a sustainable and potentially cost-effective alternative to conventional methods.
Related Concept Videos
03:00Electrolysis
27.4K
In a galvanic cell, the electrical work is done by a redox system on its surroundings as electrons produced by the spontaneous redox reactions are transferred through an external circuit. Alternatively, an external circuit does work on a redox system by imposing a voltage sufficient to drive an otherwise nonspontaneous reaction in a process known as electrolysis. For instance, recharging a battery involves the use of an external power source to drive the spontaneous (discharge) cell reaction in...
27.4K
02:47Voltaic/Galvanic Cells
58.6K
Spontaneous Chemical Reactions
Spontaneous redox reactions occur abundantly in nature. The chemical reaction occurring in a disposable AA battery powering our remote controls is one such example of a spontaneous redox reaction. Another example is the immersion of coiled copper wire into an aqueous silver nitrate solution. The reaction shows a gradual, visually impressive color change from colorless to bright blue and the formation of a grey precipitate on the copper wire. In this experiment,...
Spontaneous redox reactions occur abundantly in nature. The chemical reaction occurring in a disposable AA battery powering our remote controls is one such example of a spontaneous redox reaction. Another example is the immersion of coiled copper wire into an aqueous silver nitrate solution. The reaction shows a gradual, visually impressive color change from colorless to bright blue and the formation of a grey precipitate on the copper wire. In this experiment,...
58.6K
01:25Electric Generator: Alternator
2.6K
Electric generators induce an emf by rotating a coil in a magnetic field. A simple alternator is an AC generator that creates electrical energy that varies sinusoidally with time. A simple alternator consists of a conducting loop that is placed inside a uniform magnetic field. The loop is connected to split rings connected to the external circuit with the help of brushes.
The magnetic flux passing through the coil varies sinusoidally as the loop rotates inside the magnetic field. This...
The magnetic flux passing through the coil varies sinusoidally as the loop rotates inside the magnetic field. This...
2.6K
03:02Standard Electrode Potentials
45.2K
On comparing the reactivity of silver and lead, it is observed that the two ionic species, Ag+ (aq) and Pb2+ (aq), show a difference in their redox reactivity towards copper: the silver ion undergoes spontaneous reduction, while the lead ion does not. This relative redox activity can be easily quantified in electrochemical cells by a property called cell potential. This property is commonly known as cell voltage in electrochemistry, and it is a measure of the energy which accompanies the charge...
45.2K