How the changing environment affects solar-panel efficiency: the Indian perspective

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Hello, and welcome to the Physics World weekly

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podcast. I'm Hamish Johnston.

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Solar panels offer a way of mitigating

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climate change

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by generating

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electricity with an extremely low carbon footprint.

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Today,

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India ranks fifth amongst nations

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in terms of installed

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solar energy capacity,

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and increasing this is playing a crucial role

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in the country's drive to reduce its greenhouse

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gas emissions

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by 45%

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by 02/1930

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when compared to 02/2005.

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While much of India is blessed with abundant

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sunshine,

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the country is experiencing

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a persistent

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decline in incoming solar radiation

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associated with aerosol pollution.

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What is more, higher temperatures

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associated with climate change

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reduce the efficiency of solar cells,

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and their performance

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is also impacted

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by other climate related phenomena.

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To understand how a changing environment is affecting

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solar energy in India,

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I'm joined down the line from the Barcelona

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Supercomputing

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Center by Shashovan

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Ghose.

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He is formerly of the Center for Atmospheric

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Sciences

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at the Indian Institute of Technology,

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Delhi,

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where he coauthored a paper that looks at

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India's future

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photovoltaic

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potential.

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Hi, Shashovan.

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Welcome to the podcast.

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Thank you. Now, Shashovan, you begin your paper

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by saying that the effects of climate

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change are already creating significant

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challenges to solar power generation

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in India.

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Why is that?

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Yeah. You correctly mentioned this thing and pointed

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out. So let me talk about,

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basic understanding of, this climate change and the

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solar renewable

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energy nexus.

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So you already know that climate change is

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happening,

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and the evidence are numerous.

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Interestingly, the very solution

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to tackle the climate change is to switch

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to renewable energy.

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However,

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the renewable solar energy and other renewable energy

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to harness

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and also use the renewable energy is also

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vulnerable to the climate change. So if you

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ask me why, so let me give you

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an example in the in the case of

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solar photovoltaic.

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So for solar photovoltaic,

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surface solar radiation is the primary factor for

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our solar generation.

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But to harness that energy,

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we need solar panel.

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So this very technology

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is also vulnerable

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to the climate change consequence.

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So here, two things are are are to

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be mentioned.

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The first one is the how much amount

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of solar

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radiation

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is is is coming to the solar panel

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to produce the solar energy. And the second

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one is that when the solar panel

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l is, is exposed to the, daylight sunshine,

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how the climate change will impact that, technology

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itself.

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So there are three three factors

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which is actually playing a role all to

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the solar photovoltaic.

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One is the solar radiation,

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and then the sec second thing is that

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the temperature

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are and the wind speed, relative humidity, and

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other meteorological

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parameters. So if you look into the climate

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change landscape,

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then you see this all these factors, like

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the solar radiation,

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temperature,

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wind speed, all these things are also going

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to change. So to tackle climate change, we

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need to switch to renewable energy, but at

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the same time, we also take care of

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that how the climate change will impact these,

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primary variables,

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to better harness the solar radiation.

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So in coming to India, if you looked

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into this,

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we use the,

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climate global climate models,

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from the,

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coupled model intercomparison

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project phase,

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six, which are actually an initiative by the

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World Climate Research Program. And we also looked

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into,

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the future scenarios

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or,

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to to design in the, the input variables

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for the solar photovoltaic. And what we found

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that the the the the different solar energy

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indicators

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are going to decrease

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is in this consequence. And from that, at

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point of view, we are telling that the

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solar energy

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potential over Indian region and is expected to

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decrease in the mid century.

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So I just wanna make sure that I

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understand,

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the connection between a warming climate and the

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performance of solar cells. Are you saying that

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as the temperature increases, the ambient temperature,

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then the efficiency

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of a solar cell will drop?

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Exactly.

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You understood,

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correctly.

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So the solar panel material,

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is,

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is, is a is a subjected to

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change by the climate change consequence. The meaning

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is that the solar panel material,

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one parameter is important.

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We call this temperature coefficient of the solar

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panel material. So in the in the market,

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the the different type of solar panels, we

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we we now get. One is monocrystalline,

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then the multicrystalline,

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and, now,

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recently,

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the, thin film, solar panels. So all these

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type of solar panels have a different temperature

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coefficient. Meaning is that,

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the temperature coefficient indicates the percentage decrease in

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efficiency

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for every degree

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degree Celsius rise in temperature

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above a threshold temperature, which we call as

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25 degree centigrade.

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So for instance, if you can think of

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a panel of temperature coefficient

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of point four percentage,

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that means that the temperature is if above

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10 degree centigrade,

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from this 25 degree,

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the standard threshold, then there will be a

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a possibility that 4% decrease in efficiency.

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That means if a solar panel have a

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efficiency of 2020%,

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now it will work at 19.2.

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So so so that is the case. So

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for for to tackle this, high temperature,

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we need to produce climate resilient,

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solar panel. And for that, the thin film

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solar panels are are better preferred, and,

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and that will actually tackle this high temperature.

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And, also, along with this, we need to

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have a sufficient,

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heat exchange,

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methodology

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to the, solar panel to better,

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get the,

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solar harnessing capability.

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And and one of the key findings that

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you found in your paper

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is that,

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future solar photovoltaic potential across India

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in the period twenty forty one

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to twenty fifty

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will drop by about 3%

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when compared

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to nineteen eighty five twenty fourteen

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baseline.

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Is this is is all of that due

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to,

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temperature increase, or are there other factors involved?

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Okay. Well,

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like, in our paper,

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we actually use a PV conceptual

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model,

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which actually

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takes the input from

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the different climate,

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models output, like the solar radiation,

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wind speed,

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temperature, and other fact other variables

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to the input, to this, PV conceptual model.

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And and we get,

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the output of different solar energy indicator from

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that PV conceptual model. So one of the

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indicator is,

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PV potential,

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which is a function of radiation,

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temperature, and the surface wind speed. So let

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me clarify that this PV potential,

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has a three different,

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type of variability,

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with these three parameters.

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So if you have high radiation,

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then you get more PV potential. If you

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have high surface wind, you get better heat

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exchange from the solar panel, so you get

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more or PV, potential.

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But if you have higher temperature, then that

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leads to a drop in PV potential. So

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what we found in case of India,

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is that the drop in PV potential

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are in the mid,

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century decades

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is expected to due to

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the drop in radiation

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followed by the increasing temperature. However, the surface

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wind and has a very minimal effect.

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I see. And and India is a is

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a huge country.

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You know, you've got deserts,

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in the Northwest.

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You've got mountains.

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You've got huge cities. You've got lots of

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countryside.

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In the South Of India,

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I suppose you have a tropical climate.

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Is this

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3%,

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is that something that is going to be

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uniform across India, or are there gonna be

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some parts of the country where it's more

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than 3% and some parts that are less?

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Yeah.

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Well,

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so,

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the India is a first country, as you

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mentioned, and it has a, like,

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a, different,

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if you go from north to south or

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east to east to west,

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there is a variability in the climates and

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all these,

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factors.

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So, as you as you rightly mentioned, so

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these the the input variables for this PP

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conceptual model will vary from one parts of

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Indian,

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to the other parts of India. So what

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we found is the drop in PV potential

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is not uniform. As you mentioned that the,

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PV potential, as I already talked about, that

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is a, function of the radius and temperature

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and the surface wind wind speed. So in

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almost all part of the country,

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what we found on is the drop in

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PV potential, and this 3% is the national

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average.

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So

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and this drop in PV potential is mainly

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because of the increasing aerosol that is related

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to the higher air pollution

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and then the followed by the increasing temperature.

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So what we found is that, most part

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of the Indian nation having a drop in

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PV potential except the Northeastern region and where

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we are getting a increase in solar potential,

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and that is due to the decrease in

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00:11:05,350 --> 00:11:05,830
cloud,

288
00:11:06,230 --> 00:11:09,690
cover over those region. But interestingly, the Northwestern

289
00:11:09,830 --> 00:11:12,070
Part of India where the Thought Desert is

290
00:11:12,070 --> 00:11:13,429
there, which is,

291
00:11:13,990 --> 00:11:14,490
inherently

292
00:11:14,950 --> 00:11:15,450
inherently,

293
00:11:16,524 --> 00:11:19,485
with the high aerosol load. But what we

294
00:11:19,485 --> 00:11:20,544
found in future

295
00:11:20,845 --> 00:11:23,085
are it is expected that the cloud cover

296
00:11:23,085 --> 00:11:26,125
will increase and the aerosol load will decrease.

297
00:11:26,125 --> 00:11:28,705
So over those region, we'll be more sensitive

298
00:11:28,764 --> 00:11:31,500
to the cloud cover. So as you rightly

299
00:11:31,500 --> 00:11:32,000
mentioned,

300
00:11:32,539 --> 00:11:33,039
that,

301
00:11:33,659 --> 00:11:36,320
the PV potential the drop in PV potential

302
00:11:36,459 --> 00:11:39,339
has a regional pattern, and that is mainly

303
00:11:39,339 --> 00:11:40,639
governed by the aerosols

304
00:11:41,100 --> 00:11:43,214
and some part with the clouds and followed

305
00:11:43,214 --> 00:11:44,834
by the increasing temperature.

306
00:11:45,934 --> 00:11:49,934
Okay. And you you've just mentioned aerosols. Aerosol

307
00:11:49,934 --> 00:11:51,554
pollution is a big problem,

308
00:11:52,575 --> 00:11:54,894
in many parts of the world, and I

309
00:11:54,894 --> 00:11:55,954
think particularly

310
00:11:56,759 --> 00:11:59,740
in parts of India, for example, of Delhi.

311
00:12:01,399 --> 00:12:03,980
How how does, aerosol pollution affect

312
00:12:04,360 --> 00:12:06,139
the efficiency of solar panels?

313
00:12:07,960 --> 00:12:09,100
Well, aerosol

314
00:12:09,639 --> 00:12:12,404
are very common. Aerosol pollutions, particularly

315
00:12:12,884 --> 00:12:15,605
particularly particulate matter pollutions are very common in

316
00:12:15,605 --> 00:12:16,585
global South

317
00:12:16,965 --> 00:12:18,585
and mainly over India,

318
00:12:19,445 --> 00:12:22,805
China, and Bangladesh. And, these these are the

319
00:12:22,805 --> 00:12:23,305
countries,

320
00:12:23,764 --> 00:12:26,825
the aerosol pollutions are are are quite high

321
00:12:26,850 --> 00:12:30,309
and always in the, in the global media,

322
00:12:30,610 --> 00:12:31,110
mentions.

323
00:12:31,730 --> 00:12:34,289
So so let me just talk about the

324
00:12:34,289 --> 00:12:37,329
physics behind how aerosol will impact the solar

325
00:12:37,329 --> 00:12:37,829
radiation.

326
00:12:38,129 --> 00:12:39,909
So as you know that the aerosols,

327
00:12:40,529 --> 00:12:41,829
float over the atmospheric

328
00:12:42,615 --> 00:12:43,115
atmosphere,

329
00:12:43,495 --> 00:12:46,455
and it based on its property, it either

330
00:12:46,455 --> 00:12:49,575
scatter or absorb the incoming solar radiation reaching

331
00:12:49,575 --> 00:12:53,174
to the, solar panel and reduces the solar

332
00:12:53,174 --> 00:12:53,674
panel,

333
00:12:55,174 --> 00:12:56,394
performance efficiency.

334
00:12:57,209 --> 00:12:59,370
So what we found is that the most

335
00:12:59,370 --> 00:13:00,089
part of the,

336
00:13:00,490 --> 00:13:04,509
country, an increase in aerosol, loading is expected

337
00:13:04,889 --> 00:13:07,870
in mid century and which, will lead to

338
00:13:08,009 --> 00:13:11,024
the reduction of radiation and at the same

339
00:13:11,024 --> 00:13:13,184
time to, to lead to the,

340
00:13:13,585 --> 00:13:14,085
reduction

341
00:13:14,544 --> 00:13:15,605
in on PV potential.

342
00:13:16,464 --> 00:13:18,085
In in another paper,

343
00:13:19,024 --> 00:13:20,004
which was published,

344
00:13:20,384 --> 00:13:22,644
two years back where we quantified

345
00:13:23,105 --> 00:13:25,605
that due to aerosol, India lost almost

346
00:13:26,059 --> 00:13:28,379
one third of its solar resources in the

347
00:13:28,379 --> 00:13:30,620
last two decades from 02/2001

348
00:13:30,620 --> 00:13:32,240
to, 02/2019.

349
00:13:32,620 --> 00:13:34,480
So, yeah, aerosol pollution,

350
00:13:35,100 --> 00:13:38,159
is a big concern, for our solar photovoltaic

351
00:13:38,379 --> 00:13:38,879
potential

352
00:13:39,894 --> 00:13:42,215
in India. I see. And is it,

353
00:13:43,095 --> 00:13:45,035
is it also a problem that,

354
00:13:45,575 --> 00:13:48,215
I mean, I'm guessing that some of these

355
00:13:48,215 --> 00:13:48,715
aerosols,

356
00:13:49,735 --> 00:13:50,875
and other particulates

357
00:13:52,559 --> 00:13:54,340
will settle on,

358
00:13:56,160 --> 00:13:57,700
solar panels and,

359
00:13:58,559 --> 00:14:01,120
you know, essentially make them dirty and not

360
00:14:01,120 --> 00:14:03,600
as efficient. And you you'd have to people

361
00:14:03,600 --> 00:14:05,200
will have to go out them and go

362
00:14:05,200 --> 00:14:06,820
out there and and clean them

363
00:14:07,200 --> 00:14:07,940
more often,

364
00:14:09,004 --> 00:14:11,825
to to, to boost their efficiency. Is that

365
00:14:11,884 --> 00:14:14,945
is that also a problem with, with pollution?

366
00:14:16,045 --> 00:14:16,545
Exactly.

367
00:14:17,004 --> 00:14:17,504
Like,

368
00:14:18,445 --> 00:14:20,764
so so let me just tell you that,

369
00:14:21,085 --> 00:14:23,149
what we found is that in

370
00:14:23,529 --> 00:14:24,589
the last two years,

371
00:14:25,610 --> 00:14:27,389
we are working on these things.

372
00:14:28,009 --> 00:14:28,509
So,

373
00:14:29,449 --> 00:14:31,470
what we found that there are two mechanism

374
00:14:31,610 --> 00:14:34,829
in which aerosol is impacting the solar radiation

375
00:14:35,274 --> 00:14:38,414
and followed, the, solar photovoltaic potential.

376
00:14:38,794 --> 00:14:41,134
One is what we call this the atmospheric

377
00:14:41,274 --> 00:14:44,315
attenuation effect where the aerosols are floating over

378
00:14:44,315 --> 00:14:44,975
the atmosphere,

379
00:14:45,355 --> 00:14:47,834
and they block the solar radiation reaching to

380
00:14:47,834 --> 00:14:50,409
the solar panel. And the second, what we

381
00:14:50,409 --> 00:14:53,610
called is the, settling of aerosol over the

382
00:14:53,610 --> 00:14:56,570
solar panel, which we we we technically called

383
00:14:56,570 --> 00:14:58,970
is a soiling loss. And we found that,

384
00:14:59,210 --> 00:15:01,629
the soiling loss is, very, very,

385
00:15:02,745 --> 00:15:04,125
severe in India,

386
00:15:05,065 --> 00:15:08,125
for, the places where there are either dust

387
00:15:08,184 --> 00:15:08,684
dominated

388
00:15:09,144 --> 00:15:10,605
or, there are polluted,

389
00:15:11,065 --> 00:15:14,264
from the other, aerosol species. So as you

390
00:15:14,264 --> 00:15:17,850
rightly pointed out, there's these two factors are

391
00:15:18,089 --> 00:15:20,509
actually impacting the, solar radiation

392
00:15:21,049 --> 00:15:23,309
and and also the solar photovoltaic

393
00:15:23,690 --> 00:15:24,190
generation.

394
00:15:25,049 --> 00:15:27,209
I see. And that I mean, cleaning solar

395
00:15:27,209 --> 00:15:28,750
cells is is an important,

396
00:15:30,250 --> 00:15:32,774
issue on its own, isn't it? Because I

397
00:15:32,855 --> 00:15:35,014
mean, I'm not sure exactly how they're cleaned,

398
00:15:35,014 --> 00:15:36,934
but I suppose if you're if you're having

399
00:15:36,934 --> 00:15:39,355
to clean them regularly with lots of water,

400
00:15:39,975 --> 00:15:41,434
that could be a problem

401
00:15:42,055 --> 00:15:43,894
in in parts of the world and and

402
00:15:43,894 --> 00:15:46,774
parts of India where there isn't a lot

403
00:15:46,774 --> 00:15:49,019
of water. You know, it could put a

404
00:15:49,019 --> 00:15:51,199
strain on on local resources.

405
00:15:52,220 --> 00:15:54,480
Yeah. It is a a very fantastic,

406
00:15:55,019 --> 00:15:57,659
point you you mentioned. If you looked into

407
00:15:57,659 --> 00:16:01,100
the most of the, solar parks are are

408
00:16:01,100 --> 00:16:04,924
over the, desert region. So there is inherently,

409
00:16:05,065 --> 00:16:06,764
they are, water stressed.

410
00:16:07,065 --> 00:16:09,084
So if you do not have a proper,

411
00:16:09,544 --> 00:16:10,845
like, cleaning,

412
00:16:12,745 --> 00:16:16,105
cleaning, cleaning, requirement or maintenance, you you may

413
00:16:16,105 --> 00:16:18,684
lead, to the water stress problem.

414
00:16:19,049 --> 00:16:20,830
So so so so to

415
00:16:21,210 --> 00:16:23,690
to avoid this problem, we we need to

416
00:16:23,690 --> 00:16:24,570
focus on,

417
00:16:25,049 --> 00:16:25,950
certain coating,

418
00:16:26,409 --> 00:16:28,429
which are are, maybe,

419
00:16:28,809 --> 00:16:32,169
euphoric to this particulate matter. So they will

420
00:16:32,169 --> 00:16:34,214
not stick to the panel. And,

421
00:16:34,995 --> 00:16:37,254
so so we we have to look into

422
00:16:37,475 --> 00:16:38,274
that type of,

423
00:16:38,754 --> 00:16:39,254
resilient,

424
00:16:40,674 --> 00:16:41,174
technology

425
00:16:41,875 --> 00:16:43,575
before the, solar panels.

426
00:16:44,274 --> 00:16:46,115
I see. And and I would imagine in

427
00:16:46,115 --> 00:16:48,519
in other parts of India where, you know,

428
00:16:48,519 --> 00:16:50,539
let's say it's it's very wet,

429
00:16:51,080 --> 00:16:53,159
you might have the opposite problem in the

430
00:16:53,159 --> 00:16:53,879
sense that,

431
00:16:54,519 --> 00:16:56,220
because you've got so much water

432
00:16:56,600 --> 00:16:57,899
around, you're getting,

433
00:16:58,919 --> 00:17:01,500
I don't know, things like moss and lichen

434
00:17:02,134 --> 00:17:03,754
growing on the solar panels.

435
00:17:04,775 --> 00:17:06,375
And, you know, you have to go out

436
00:17:06,375 --> 00:17:09,035
and and clean that material off.

437
00:17:09,575 --> 00:17:12,855
Yeah. Exactly. This atmospheric variable, if I correctly

438
00:17:12,855 --> 00:17:15,910
understood your point that, the high humidity and

439
00:17:15,910 --> 00:17:17,990
all these things can lead to algae and

440
00:17:17,990 --> 00:17:21,190
other, things to grow over the, solar panels.

441
00:17:21,190 --> 00:17:23,990
So, yeah, that that could be also a

442
00:17:23,990 --> 00:17:26,630
factor. So so the all these things comes

443
00:17:26,630 --> 00:17:27,130
under,

444
00:17:27,494 --> 00:17:29,974
what we call the soiling of the, solar

445
00:17:29,974 --> 00:17:30,474
panels.

446
00:17:30,855 --> 00:17:33,355
So in in one of my future,

447
00:17:33,815 --> 00:17:37,015
work is on that, lineup where we are

448
00:17:37,015 --> 00:17:41,355
actually working on this, soiling sorts of, problem,

449
00:17:41,789 --> 00:17:44,750
and, we are trying to provide some sorts

450
00:17:44,750 --> 00:17:45,250
of,

451
00:17:46,110 --> 00:17:46,610
periodic,

452
00:17:47,150 --> 00:17:49,789
periodicity of the cleaning cycle, what should be

453
00:17:49,789 --> 00:17:53,710
the proper, cleaning cycle period to to get

454
00:17:53,710 --> 00:17:56,714
a better performance, to better assess the solar

455
00:17:56,714 --> 00:17:57,214
energy,

456
00:17:57,914 --> 00:17:58,414
generation.

457
00:17:59,194 --> 00:18:01,835
And I suppose we've talked a a little

458
00:18:01,835 --> 00:18:04,714
bit about how solar technologies can be made

459
00:18:04,714 --> 00:18:05,214
resilient

460
00:18:05,755 --> 00:18:08,575
to the effects of climate change in India

461
00:18:08,634 --> 00:18:09,375
and elsewhere.

462
00:18:09,990 --> 00:18:12,630
What what what are the main things that

463
00:18:12,630 --> 00:18:13,930
that need to be done,

464
00:18:14,549 --> 00:18:16,869
you know, when we're thinking about what types

465
00:18:16,869 --> 00:18:17,609
of solar

466
00:18:17,990 --> 00:18:19,990
panels we should use and how we should

467
00:18:19,990 --> 00:18:22,184
maintain them? What are the big things that

468
00:18:22,184 --> 00:18:23,224
we can do to,

469
00:18:24,024 --> 00:18:25,484
make the systems resilient

470
00:18:26,024 --> 00:18:27,724
to increasing temperatures?

471
00:18:28,825 --> 00:18:29,325
Yeah.

472
00:18:29,704 --> 00:18:32,204
So so there are, there are actually,

473
00:18:33,224 --> 00:18:34,284
two, three things,

474
00:18:35,144 --> 00:18:38,099
could be the main features to look into

475
00:18:38,099 --> 00:18:39,320
the future solar,

476
00:18:39,859 --> 00:18:42,900
technology in terms of climate resilient to make

477
00:18:42,900 --> 00:18:44,039
it climate resilient.

478
00:18:44,820 --> 00:18:46,119
One could be the,

479
00:18:46,740 --> 00:18:48,839
temperature coefficient of the material,

480
00:18:49,539 --> 00:18:52,184
which I already mentioned you. Like, we need

481
00:18:52,184 --> 00:18:55,865
to think about, like, the material which has

482
00:18:55,865 --> 00:18:58,585
a a less temperature coefficient. Meaning is that

483
00:18:58,585 --> 00:19:00,365
every degree rise in temperature

484
00:19:00,744 --> 00:19:03,565
from a threshold like 25 degree centigrade,

485
00:19:04,829 --> 00:19:05,309
the,

486
00:19:05,710 --> 00:19:09,089
drop in PV potential efficiency should be less.

487
00:19:09,470 --> 00:19:11,009
So so for this,

488
00:19:11,470 --> 00:19:13,069
there are three three, four,

489
00:19:13,470 --> 00:19:14,849
type of solar panels,

490
00:19:15,230 --> 00:19:16,450
material like monocrystalline,

491
00:19:17,505 --> 00:19:18,005
multicrystalline,

492
00:19:18,384 --> 00:19:20,224
and the thin film. And what we found

493
00:19:20,224 --> 00:19:21,525
is that the thin film,

494
00:19:21,984 --> 00:19:22,884
solar cells

495
00:19:23,345 --> 00:19:23,744
have,

496
00:19:24,305 --> 00:19:25,845
less temperature coefficient.

497
00:19:26,625 --> 00:19:29,025
So meaning is that if there is high

498
00:19:29,025 --> 00:19:30,230
temperature, or,

499
00:19:31,169 --> 00:19:31,669
increment

500
00:19:32,049 --> 00:19:33,990
from the threshold limit,

501
00:19:34,609 --> 00:19:35,890
they will not get,

502
00:19:37,250 --> 00:19:40,769
more efficiency drop. So so that efficiency drop

503
00:19:40,769 --> 00:19:42,974
for high temperature will be less for the,

504
00:19:43,375 --> 00:19:44,195
thin film

505
00:19:44,815 --> 00:19:45,394
solar cell.

506
00:19:45,695 --> 00:19:47,315
And the second thing is that,

507
00:19:47,695 --> 00:19:48,755
to avert the,

508
00:19:49,214 --> 00:19:49,714
solar,

509
00:19:50,174 --> 00:19:51,154
soiling losses,

510
00:19:51,695 --> 00:19:53,474
we need to thought thought about,

511
00:19:53,934 --> 00:19:55,234
certain coating materials,

512
00:19:55,919 --> 00:19:58,799
which are at the same time high heat

513
00:19:58,799 --> 00:19:59,299
resistive,

514
00:19:59,759 --> 00:20:00,980
and, also,

515
00:20:01,519 --> 00:20:04,240
they will not allow to stick to the

516
00:20:04,319 --> 00:20:05,539
stick to different,

517
00:20:06,079 --> 00:20:07,279
particular matter,

518
00:20:07,759 --> 00:20:10,394
if if there is. So so so do

519
00:20:10,474 --> 00:20:13,194
these two, three things we need to think

520
00:20:13,194 --> 00:20:13,694
about

521
00:20:13,994 --> 00:20:16,794
one for to tackle the, climate change in

522
00:20:16,794 --> 00:20:17,774
terms of temperature

523
00:20:18,234 --> 00:20:20,654
and the, particulate matter pollution.

524
00:20:21,194 --> 00:20:23,514
And and when you're looking at these different

525
00:20:23,514 --> 00:20:24,014
technologies,

526
00:20:24,690 --> 00:20:26,690
is there is it the case that there's

527
00:20:26,690 --> 00:20:29,269
a trade off that if you want,

528
00:20:30,210 --> 00:20:32,210
if you want to make a a solar

529
00:20:32,210 --> 00:20:33,429
panel that's resilient

530
00:20:34,130 --> 00:20:36,309
to increasing temperatures, then

531
00:20:37,250 --> 00:20:39,909
it has to be more expensive than existing

532
00:20:40,985 --> 00:20:41,485
technologies,

533
00:20:41,945 --> 00:20:43,805
or perhaps it's not as efficient

534
00:20:44,664 --> 00:20:45,725
as existing

535
00:20:46,505 --> 00:20:47,005
technologies?

536
00:20:47,384 --> 00:20:49,384
Or are you confident that you can come

537
00:20:49,384 --> 00:20:49,945
up with,

538
00:20:50,585 --> 00:20:51,404
with photovoltaic

539
00:20:52,825 --> 00:20:53,325
photovoltaics

540
00:20:53,865 --> 00:20:54,605
that are

541
00:20:54,990 --> 00:20:56,529
both resilient and

542
00:20:56,910 --> 00:20:58,529
efficient and low cost.

543
00:20:59,869 --> 00:21:00,769
Yeah. Obviously,

544
00:21:01,309 --> 00:21:04,369
when you have all these, things you incorporate

545
00:21:04,430 --> 00:21:07,549
in one material, which you are, trying to

546
00:21:07,549 --> 00:21:08,049
prepare,

547
00:21:08,744 --> 00:21:11,164
that will comes with an, with a cost.

548
00:21:11,305 --> 00:21:14,025
So so so so that needs to be,

549
00:21:14,025 --> 00:21:16,345
like, we need to we need to thought

550
00:21:16,345 --> 00:21:17,404
of, these,

551
00:21:17,785 --> 00:21:20,585
these these things. But but what I what

552
00:21:20,585 --> 00:21:22,525
I found from the studies

553
00:21:23,149 --> 00:21:26,589
and from my, PhD thesis is that, like,

554
00:21:26,589 --> 00:21:27,490
if you want,

555
00:21:27,869 --> 00:21:28,609
to have

556
00:21:29,389 --> 00:21:30,769
a better utilization

557
00:21:31,069 --> 00:21:31,730
of solar,

558
00:21:32,509 --> 00:21:33,009
potential,

559
00:21:34,269 --> 00:21:35,089
we need,

560
00:21:35,470 --> 00:21:38,525
two things. One is that we need to

561
00:21:38,744 --> 00:21:39,884
clean our environment.

562
00:21:40,585 --> 00:21:43,404
So the clean air should come

563
00:21:43,785 --> 00:21:45,965
hand to hand with the clean energy.

564
00:21:46,585 --> 00:21:48,125
So if you clean your environment,

565
00:21:48,424 --> 00:21:50,585
then what will happen, you are coming up

566
00:21:50,585 --> 00:21:50,970
with

567
00:21:51,450 --> 00:21:51,929
less,

568
00:21:52,329 --> 00:21:53,789
a particulate matter pollution.

569
00:21:54,169 --> 00:21:55,230
So you get

570
00:21:55,529 --> 00:21:59,230
more solar radiation impinge into the solar panel

571
00:21:59,450 --> 00:22:01,150
to produce more solar energy.

572
00:22:01,690 --> 00:22:03,849
But at the same time, if you also

573
00:22:03,849 --> 00:22:04,589
look into

574
00:22:04,994 --> 00:22:07,795
all the climate action, if you have a

575
00:22:07,795 --> 00:22:09,174
strict climate action,

576
00:22:09,634 --> 00:22:12,434
then what will happen? You will avoid the

577
00:22:12,434 --> 00:22:14,295
temperature induced losses.

578
00:22:14,755 --> 00:22:17,174
So the PV panel will work,

579
00:22:19,210 --> 00:22:20,430
its rated efficiency

580
00:22:21,049 --> 00:22:22,670
so you get better,

581
00:22:23,210 --> 00:22:24,750
solar energy generation.

582
00:22:25,289 --> 00:22:26,589
So so for me,

583
00:22:27,450 --> 00:22:28,829
we need strict

584
00:22:29,369 --> 00:22:30,109
air pollution,

585
00:22:31,174 --> 00:22:31,674
mitigation.

586
00:22:32,134 --> 00:22:34,134
And at the same time, we also need

587
00:22:34,134 --> 00:22:36,394
strict climate action to better,

588
00:22:37,255 --> 00:22:37,755
utilize

589
00:22:38,295 --> 00:22:39,355
the PV potential

590
00:22:40,055 --> 00:22:42,555
and to make a sustainable lesson.

591
00:22:43,575 --> 00:22:44,234
I see.

592
00:22:44,740 --> 00:22:46,899
Well, that's great. Thanks thanks so much for

593
00:22:46,899 --> 00:22:48,279
coming on the podcast

594
00:22:48,579 --> 00:22:51,380
and, and talking about this. It's a really

595
00:22:51,380 --> 00:22:51,880
fascinating

596
00:22:52,339 --> 00:22:52,839
subject.

597
00:22:53,460 --> 00:22:53,960
Sushovan's

598
00:22:54,259 --> 00:22:55,799
paper is called Future

599
00:22:56,099 --> 00:22:56,599
Photovoltaic

600
00:22:57,140 --> 00:22:58,519
Potential in India,

601
00:22:59,014 --> 00:23:02,855
navigating the interplay between air pollution control and

602
00:23:02,855 --> 00:23:04,234
climate change mitigation.

603
00:23:04,774 --> 00:23:06,714
And you can find it in the journal

604
00:23:06,934 --> 00:23:07,434
Environmental

605
00:23:08,054 --> 00:23:09,194
Research Letters,

606
00:23:09,494 --> 00:23:12,394
which is published by IOP Publishing,

607
00:23:13,014 --> 00:23:15,330
which also brings you Physics

608
00:23:15,710 --> 00:23:17,650
World. Thanks for coming on the podcast.

609
00:23:18,509 --> 00:23:20,369
Thank you, doctor Hamish, for the opportunity.

610
00:23:27,845 --> 00:23:29,605
I'm afraid that's all the time we have

611
00:23:29,605 --> 00:23:33,065
for this week's podcast. Thanks to Shoshovan Ghos

612
00:23:33,125 --> 00:23:35,924
for joining me today, and a special thanks

613
00:23:35,924 --> 00:23:37,865
to our producer, Fred Isles.

614
00:23:38,404 --> 00:23:40,539
We'll be back again next week, But in

615
00:23:40,539 --> 00:23:41,119
the meantime,

616
00:23:41,420 --> 00:23:43,359
do check out the latest episode

617
00:23:43,660 --> 00:23:46,000
of the Physics World Stories podcast,

618
00:23:46,539 --> 00:23:49,519
which looks back a century to the birth

619
00:23:49,579 --> 00:23:51,680
of modern quantum theory.

620
00:23:52,555 --> 00:23:54,414
In 1925,

621
00:23:54,634 --> 00:23:55,295
the physicist

622
00:23:55,835 --> 00:23:56,974
Werner Heisenberg

623
00:23:57,674 --> 00:24:00,894
holidayed on the German island of Helgoland

624
00:24:01,755 --> 00:24:02,894
seeking respite

625
00:24:03,195 --> 00:24:04,894
from his pollen allergy.

626
00:24:06,009 --> 00:24:07,309
There, he formulated

627
00:24:08,009 --> 00:24:09,150
matrix mechanics,

628
00:24:09,609 --> 00:24:11,390
which provided a mathematical

629
00:24:11,930 --> 00:24:12,430
framework

630
00:24:12,809 --> 00:24:13,549
for describing

631
00:24:14,009 --> 00:24:14,829
the curious

632
00:24:15,369 --> 00:24:15,869
observations

633
00:24:16,329 --> 00:24:17,630
of quantum physics.

634
00:24:18,569 --> 00:24:19,470
This June,

635
00:24:19,875 --> 00:24:22,134
physicists will gather on Helgoland

636
00:24:22,674 --> 00:24:24,295
for a six day workshop

637
00:24:24,674 --> 00:24:25,734
that will celebrate

638
00:24:26,195 --> 00:24:26,695
Heisenberg's

639
00:24:27,234 --> 00:24:28,454
historic breakthrough.

640
00:24:29,555 --> 00:24:32,055
The podcast features three physicists

641
00:24:32,490 --> 00:24:34,430
who are involved in the workshop.

642
00:24:35,210 --> 00:24:38,089
They share their insights on the current state

643
00:24:38,089 --> 00:24:40,029
of quantum science and technology,

644
00:24:41,049 --> 00:24:42,829
discussing the latest developments

645
00:24:43,210 --> 00:24:46,109
in quantum sensing, quantum information,

646
00:24:46,410 --> 00:24:47,869
and quantum computing.

647
00:24:48,704 --> 00:24:50,884
They also reflect on the significance

648
00:24:51,265 --> 00:24:52,724
of attending a conference

649
00:24:53,105 --> 00:24:56,164
at a location that is so deeply ingrained

650
00:24:56,704 --> 00:24:58,964
in the story of quantum mechanics.

651
00:24:59,825 --> 00:25:03,299
Talks at the event will span the science

652
00:25:03,299 --> 00:25:05,480
and history of quantum theory,

653
00:25:06,019 --> 00:25:09,159
as well as the nature of scientific

654
00:25:09,460 --> 00:25:09,960
revolutions.

655
00:25:10,819 --> 00:25:13,380
You can listen to that episode of the

656
00:25:13,380 --> 00:25:14,440
Stories podcast

657
00:25:14,740 --> 00:25:16,599
on the Physics World website

658
00:25:17,174 --> 00:25:20,075
or at your favorite podcast provider.

659
00:25:21,015 --> 00:25:22,315
It's called Helgoland,

660
00:25:23,095 --> 00:25:24,235
leading physicists

661
00:25:24,695 --> 00:25:28,075
to gather on the tiny island where quantum

662
00:25:28,134 --> 00:25:29,595
mechanics was born.