Spray Painting the future of energy

Spray-on perovskite solar cells

Jennifer Bayley

DECEMBER 9, 2016

Table of Contents

Executive Summary ……………………………………………………………………… 2

Glossary ……………………………………………………………………………………….. 3

1. Introduction …………………………………………………………………………………. 4

2. Current Solar Energy Technology …………………………………………………. 5

2.1. Silicon Solar Cells …………………………………………………………………… 5

2.2. Perovskite Solar Cells …………………………………………………………….. 5

3. Spray-On Perovskite Solar Cells ……………………………………………………. 6

3.1. Overview ……………………………………………………………………………….. 6

3.2. Manufacturing Process ………………………………………………………….. 6

3.3. Comparison with Current Manufacturing ………………………………. 7

4. Features and Benefits ...………………………………………………………………… 7

4.1. Versatility ………………………………………………………………………………. 7

4.2. Costs ……………………………………………………………………………………… 8

5. Conclusion ……………………………………………………………………………………. 9

Reference List ………………………………………………………………………………. 10

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Executive SummaryThe purpose of this document is to inform investors and research developers of the green energy sector about an innovation in the manufacturing and creation of solar panels, the Spray-On Perovskite Solar Cell process.

Key TrendsSolar Energy is a vital part the renewable energy sector and the sale of solar production technology has grown in recent years due to the growing cost of fossil fuels. Manufacturing solar energy technology faster, cheaper, and more efficiently is important to the future of renewable energy. Current Solar Energy technology is mainly Solar Panels, which consist of hundreds or thousands of Solar Energy Cells laid out in an array. There are two main types of photovoltaic material that solar cells are constructed of today: silicon, and perovskite.

Spray-On Perovskite Solar Cell

The Spray-on Perovskite Solar Cell is a solar cell solar power generating surface which functions by using a liquid perovskite mineral compound as the photo-voltaic layer, which then is spray coated onto a plastic backing using a common air-based process.

Created in 2014 by researchers at the University Of Sheffield, UK. The spray-on application can be done by a simple air–based process such as: vehicle colour painting, house painting.Lower production cost due to combination of:

Perovskite material and spray-painting.

Features and BenefitsThe Perovskite photovoltaic layer is Versatile because it can be deposited:

1. In different sized layers or patterns 2. On any surface such as: cars, roofs, curved surfaces 3. Or re-deposited to fix any degradation due to weather

Lower production Costs will occur due to the smaller amount of time required to manufacture the spray-on perovskite solar cell using the combination of perovskite photovoltaic material and spray painting.

It uses common commercial grade spray painters

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Has a low materials costs

Spray-On Perovskite Solar Cells are: Low cost, Versatile, and Scalable to large volume manufacturing.

Glossary

Term DefinitionSolar Cell This is a solar power generating

surface which functions by using photovoltaic material to capture the energy of the sun and transform it into electricity.

Photovoltaic This is the conversion of light into electricity using semiconducting materials that cause them to absorb photons of light and release electrons.

Semiconducting Material This is a crystalline substance that naturally conducts electricity, such as silicon.

Wet chemistry This is the use of classical methods commonly using glassware, such as: beakers and graduated cylinders to conduct chemical interactions. It is called wet chemistry because it commonly analyzes liquids, and it is not performed with any advanced instruments or facilities.

Clean Room This is a room which is used in laboratory work and in the production of precision parts for electronic or aerospace equipment that must be maintained free of contaminants, such

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as dust or bacteria using vacuum techniques.

1.0 Introduction

The purpose of this document is to inform investors and research developers of the green energy sector about an innovation in the manufacturing and creation of solar panels. This innovation is the Spray-On Perovskite Solar Cell process.

The demand and cost of fossils fuels, such as gas and coal, will grow as the world uses up these limited resources. This will mean that in the near future more pressure will be put on renewable energy sources to become cheaper and more efficient to produce. Solar Energy is a vital part the renewable energy sector and the sale of solar production technology has grown in recent years. The International Energy Agency projects that by the year 2050, solar power will contribute 16 % of the world’s electricity [1]. At the moment, the time and cost to produce solar energy panels is barely equal to the power they produce, which slows down investment in this important resource. Manufacturing solar energy technology faster, cheaper, and more efficiently is important to the fulfillment of future energy consumption needs.

This document will cover:

The current methods in Solar Energy Cell construction

Introduce a new Solar Cell manufacturing process

Cover the cost and benefits involved with this new process

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2.0 Current Solar Energy TechnologyCurrent Solar Energy technology is mainly Solar Panels, which consist of hundreds or thousands of Solar Energy Cells laid out in a rectangular grid pattern. These solar energy cells create an electric current through the absorption of photons found in sunlight; these photons excite the movement of electrons in a semi conducting photovoltaic material, which creates an electric charge.

There are two main types of photovoltaic material that solar cells are constructed of today: silicon, and perovskite.

2.1 Silicon Solar CellsSilicon is a metalloid element paired with oxygen to form silicon dioxide (SiO2), more commonly known as silica. It was discovered in 1824 by Swedish Chemist Jöns Jacob Berzelius, and is a common component of white quartz sand found on most beaches around the world. Silicon is a type of metalloid that has properties of both metals and non-metals, and it conducts electricity, that increases in effectiveness as temperatures rise. The first silicon solar cell based was built in 1888 by Russian physicist Aleksandr Stoletov and uses thin layers of Silicon (Si) Crystals as the photovoltaic semiconducting material. Silicon solar cells account for around 90% of the worldwide solar cell production and are the most efficient at transforming solar power into electricity.

2.2 Perovskite Solar Cells

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Diagram 1: Silicon Solar Cell

Diagram 2: Perovskite Solar Cell

Perovskite is a calcium titanium oxide mineral (CaTiO3) which is crystalline in structure. It was discovered in 1839 in the Ural Mountains and named for Lev Perovski, who was a Russian mineralogist. Perovskite is created in the earth’s mantle, and is found in numerous rock and mineral formations such as limestone, igneous, and alkaline minerals. Perovskite is mined all over the world, from a broad range of different locations including the Ural and Swiss mountain ranges, Arkansas, and the volcanic deposits Mount Vesuvius. The Journal of the American Chemical Society documented the first manufactured perovskite based solar cell in 2009. Researchers at the University of Oxford refined this process in 2012 by increasing solar cell efficiency, and the search for new manufacturing techniques is currently ongoing. Due to its much easier manufacturing method than silicon, perovskite is quickly rising in popularity in the production of solar cells.

3.0 Spray-on Perovskite Solar CellsThe spray-on perovskite solar cell is a solar cell solar power generating surface which functions by using a liquid perovskite mineral compound as the photo-voltaic layer, which then is spray coated onto a plastic backing using a common air-based process. I will give a background overview of the spray-on perovskite solar cell, show the process in which this solar cell is manufactured, and then compare this process against the traditional silicone based solar cell creation model.

3.1 OverviewThis manufacturing method was created in 2014 by researchers at the University of Sheffield in Great Britain; this was joint development between the Department of Physics and Astronomy, and the Department of Chemical and Biological Engineering. The researchers use a halide-perovskite chemical mixture for the semiconducting layer, which can be processed in to a liquid that is able to be sprayed onto the solar cell base. The spray-on application can be done by a simple air–based process such as a commercial vehicle colour painting, or a house painting apparatus. The efficiency of solar energy production by this solar cell is only 11%, which is half of the 25% efficiency that traditional silicon solar cells produce; however, it has a significantly lower production cost due to the combination of using perovskite and commercial spray-painting technology.

3.2 Manufacturing Process

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Diagram 3: Spray-On Manufacturing Process

1. Perovskite photovoltaic material created using simple wet chemistry

techniques

2. Liquid placed in commercial grade air-based spray

painter

3. Material deposited on the solar cell base in

programmed layers or pattern

4. Process repeated as necessary

3.3 Comparison with current solar cell

manufacturing methods

Table 1: New Manufacturing Methods versus Traditional Manufacturing

Solar Cell Type Spray-on Perovskite Traditional SiliconElectricity Generation Low efficiency, 11% energy

productionHigh efficiency, 25% energy production

Production Facilities Traditional Lab, simple requirements for spray painting

Clean Room, high vacuum conditions required

Process Complexity Simple wet chemistry process, low temperatures needed

Multiple steps, high temperatures needed: over 1000°Kelvin

Durability Low durability, no studies done High durability, 25 years

4.0 BenefitsThis new spray-on perovskite solar cell manufacturing process will benefit the renewable energy sector by showing extreme versatility in its usage and by cutting the cost in time of solar cell production.

4.1 VersatilityThe spray-on aspect of the semiconducting layer in the perovskite solar cell is the driving force behind its versatility. This is because the Perovskite photovoltaic layer can be deposited:

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Commercial Spray Painter

Liquid Perovskite Material

Solar Cell Plastic Base

Pictures 1, 2, 3: Product Versatility

In many different layers or patterns to create solar panel arrays in a variety of sizes and shapes. On any surface that the plastic backing can be applied; such as cars, roofs, and even curved surfaces.Or re-deposited upon existing solar cells to fix any degradation the perovskite material might encounter due to normal wear and weather conditions.

4.2 CostsCreating a solar cell takes time and requires a multi-step process. Using a combination of perovskite and spray painting, lower production costs will occur due to the smaller amount of time required to manufacture the spray-on perovskite solar cell. Traditional silicon solar cells require energy-intensive crystal growth and vapor deposition methods, and a relatively thick layer of brittle silicon to be supported by a heavy piece of rigid glass.

Chart 1: Comparing Complexity of Manufacturing Process

Silicon Solar Cell Spray-On Perovskite Solar Cell

The new spray-on process is quicker and will lower the price of solar power because:

It uses common commercial grade spray painters Which can be tailored for high volume manufacturing

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Highly Complex

Rigid Glass

Thick Brittle Layers

Simple Procedure

Thin Plastic Film

Spray Painted Liquid

Photovoltaic Material Solar Cell Base Application of Material to Base

Has a low materials costs Which results in a low product sale price

5.0 ConclusionIn conclusion, I will give a quick summary of all points discussed in this document and provide a call to action for its readers to follow.

5.1 SummarySolar Energy Technology has changed rapidly due to the energy demand placed on diminishing fossil fuels, such as: gas and coal. Future energy consumers want low-cost ways to implement solar power on a large scale. At the moment, there are two types of solar cell on the market; silicon and perovskite.

This new process of manufacturing perovskite solar cells features spray painting the photovoltaic layer into the solar cell base. It is an easier and quicker way to create solar energy cells, which will cut the overall cost of production. The spray-on process is flexible and versatile, as the liquid perovskite mixture can be deposited in a variety of ways.

Overall the spray-on perovskite solar cell is:

Low cost Versatile Scalable to large volume manufacturing

5.2 Call to ActionTo learn more about the Spray-On Perovskite Solar Cell and its various applications to the renewable energy sector contact:

The University of Sheffield

Hannah PostlesMedia Relations OfficerUniversity of Sheffield

0114 222 1046 h.postles@sheffield.ac.uk

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Reference List[1] Borghino, Dario (18/05/2014). “Spray-on perovskite PV cells could slash the cost of solar electricty:, Atlas News [Online]. Available: newatlas.com/spray-on-perovskite-solar-cells/33383

[2] Web Mineral. “Perovskite Mineral Data”, webmineral.com [Online]. Available: webmineral.com/data/Perovskite.shtml

[3] The University of Sheffield. “Scientists develop pioneering new spry-on solar cells”, sheffield.ac.uk [Online]. Available: sheffield.ac.uk/news/nr/spray-on-solar-cells-1.392919

[4] The University of Sheffield. “Solar cell fabrication is simplified by spray painting”, sheffield.ac.uk [Online]. Avaliable: sheffield.ac.uk/news/nr/solar-photovoltaic-pv-spray-painting-lidzey-1.251912

[5]Wikipedia, the free encyclopedia. “Perovskite”, en-wikipedia.org [Online]. Available: en-wikipedia.org/wiki/Perovskite

[6] Wikipedia, the free encyclopedia. “Perovskite solar cell”, en-wikipedia.org [Online]. Available: en-wikipedia.org/wiki/Perovskite-solar-cell

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