I am a solar evangelist by profession, and a realist by nature.

Not the best DNA to sleep in peace, but let’s just say this has made me write this post.

Having worked in almost all main alternative energy sectors (solar, wind, biomass, biofuels, small hydro and waste to energy) in the last 10 years, I can say with confidence that solar is by far the most effective of all – it is the energy source of the future. By 2020, solar will have overtaken wind as the world’s largest alternative energy source, and by 2050, it will likely be the single largest energy source, renewable or otherwise.

All’s indeed going well for solar, and going by the hype around it (some of it justified), one could be led to thinking solar can do wonders unimaginable.

Sure, solar is a remarkable renewable energy source, but it has its limitations – else every home and factory worldwide would be running on solar.

At Solar Mango, we expect some of the limitations (especially those that are technology-dependent) to go away over the next five years, but it is important to get a dispassionate idea of what solar can, and what it cannot, at this point in time.

Here we go.

A couple of quick points before we start: One, for those curious to know a bit more, don’t forget to click the links I have provided all along – some of the links lead to really interesting stuff, I can assure you. Two, while this is a post about solar energy in general, most of it is specifically about solar photovoltaic (PV) power, as this is the real growth story.

What Solar Can, Today

  • Can compete with fossil power on costs, in select cases – There is no one cost for solar power. The actual cost depends on a number of factors – region, technology used, scale and more. Broadly however, it is clear that solar power is already cost effective against conventional grid power in select cases, and will be competitive against it power in a majority of cases by 2020 (predictions on solar “grid parity” – by Deutsche Bank and ILSR). This means that now or very soon, solar power will be economically viable to your business or household.
  • Can provide true distributed generation – This is where solar blows every other energy source away to smithereens. Owing to its modularity (here are some really small solar cells and…the world’s largest solar PV farm), and its flexibility, solar can pretty much fit anywhere – and I mean anywhere. I do not know of any other energy source that can provide energy in such a remarkably distributed way – from your rooftop, from your laptop, from hilltops, mall tops, from yacht-tops, on lake tops, on donkey, yes donkey top, any freaking-top, on your back yard, dump yards, grave yards, on water pumps, on lanterns and streetlights, mobiles, handbags

Africa’s Maasai Women and their donkey-top solar

The emancipating power of solar

  • Shave peak loads – This benefit of solar is often ignored. In many parts of the world, use of solar energy can reduce expensive power generation during peak times – times when power plants need to run costly temporary generators (based on natural gas or diesel) to match that temporary spike in demand. One such spike happens during sunshine hours in many regions. By reducing the load on the conventional power generators during such times, solar can bring down the overall cost of electricity for the region. A similar argument can be made about solar cutting down the use of diesel based back-up power generation in industrial setups, though our research has suggested that with the current tech advances in diesel generator sets and inverters, such reduction might not amount to more than 40% of total diesel consumed in most cases.
  • Can make significant contributions to fighting climate change – The world emits about 35 billion tons of CO2 every year, the primary greenhouse gas – power plants alone emit about 10 billion tons of this. A 1 MW of solar (PV) power plant can conservatively offset about 500 tons of CO2 annually – this would have been the amount of CO2 emitted by conventional thermal power plants otherwise (see the CO2 Reduction Calculator). At the current global installed capacity of 200,000 MW of solar power, it is thus already offsetting over 100 million tons of CO2 a year, a modest but not insignificant amount. This offset will be nearing 400 million tons of annual CO2 offset by 2020 and close to a billion tons of CO2 by 2025, a significant contribution. By 2050, solar PV and solar thermal combined could reduce over 6 billion tons of CO2 by 2050, says an estimate by IEA – super!
  • Provide diverse business and career opportunities – Solar energy is more than just a bunch of solar panels on rooftops or large farms. There are exciting opportunities for a range of  entrepreneurs and professionals – in design of high efficiency solar cells and power plants, in high end semiconductor research, in investment banking for large solar farm financing, in innovative storage solutions for large-scale solar, in thermal engineering in concentrating solar power (CSP), in consumer products where integrating solar power is becoming part of the wearables revolution (see also this from Swarovski), in power electronics to design next generation inverters, in policy making at local and central levels of government, in material sciences (see this and this), in sales and marketing…it is a pretty new world of biz and career opportunities!

All the stuff above are not just possible, they are all happening already.

Quite impressive for an energy source whose growth started barely five years back, isn’t it?


Now, to do justice to the statement I made about myself being a realist, I should also point out stuff that solar can’t.

What Solar Can’t (at least right now)

  • Does not provide a strong enough business case for residential sector – If your house is being powered by a reliable and stable grid at reasonable power prices, solar does not yet provide a strong enough business case on its own, for most regions worldwide. Sure, there are millions of homes putting up solar on their rooftops, but they are either subsidised by government incentives, a small percentage is forced by government mandates, and another small % of homes is going solar because they want to be green. Thus, while businesses derive a number of tangible and intangible benefits from going solar and hence have a reasonably strong business case, for residences with healthy and affordable grid power, rooftop solar without outside support is not yet attractive (for quick reference, solar power from rooftop costs about 10-15 US cents/kWh without any subsidies and other incentives, based purely on today’s costs of components, installations and interest cost on loans). We expect solar to be cost effective for a large % of residential sector worldwide by 2018.
  • Cannot provide all the electricity your house or factory needs right from your premises – Unless you are really lucky, or reasonably rich, or weird, or a nerd, or have very tolerant family members, it will be difficult for you to have your rooftop solar power all your loads and live off the grid. Don’t let that oddball tree-hugger convince you that having a house run on 100% solar is easy – it is possible, but it sure is not easy. In sum, the ordinary me and you will find it mighty difficult to live off the grid, just on solar power. For businesses that are willing to put up a solar power plant outside their premises (in a barren land outside their city for instance, and wheeling the power generated to their premises), it is quite possible even today to have 100% of their electricity supplied by solar.

You can technically live completely cut off from the grid, but practically…

  • Cannot generate electricity round the clock  in large scale– Unless we put solar power plants in space (rather futuristic with current technology, though China doesn’t think so), they cannot generate electricity 24X7 on a large scale. But is it possible for large solar farms to use some sort of storage to make solar a 24X7 baseload power source? With the current advances in and economics of storage technology, for large scale solar power plants, battery storage or even any other type of storage simply a no-no-no, so solar is not a 24X7 option at all at utility scale. (To be fair, there are indeed a few MW scale solar plants experimenting with battery storage, but these are very select cases operating on nascent business models)
  • Cannot provide power when the grid does not work, in some configurations – It is funny, but the most commonly used rooftop solar system, called the grid-tied solar, does not work when the grid does not work. There are some key technical and operational reasons why it does not, but whatever these are, it makes some people in countries with unreliable grid power wonder what the point of solar is if it does not work when there is no power from the grid. Some latest developments from inverter manufacturers such as SMA show some promise to overcome this challenge, but it is really early days yet.
  • Cannot solve the world’s power needs for quite a while – Solar power currently contributes about 1% of the world’s total electricity needs. That’s a really small %, especially when seen against the amount of noise made about solar, right? The % is likely to increase to about 2.5% by 2020 and about 4% by 2025. Estimates are difficult to come by beyond 2025, but some long range estimates by IEA predict solar to be the world’s dominant energy source by 2050. Could solar (PV+ thermal combined) be contributing close to 30% by 2050, as IEA predicts? Who knows? What we know for sure is 2050 is 35 years away, and that solar will play only a marginal role as an overall energy source at least until 2025.

27% will be supplied by solar, but it’s gonna take a while to get there

All right, so the self-proclaimed solar guru has spoken.

So, what do the Can and Can’ts of solar mean to you and me?

If you are looking at having a solar on your rooftop as a residential or business property owner, you can expect solar to satisfy part of your requirements, but most likely not all your requirements. If you wish to have your facility 100% powered by solar, the likely way forward will be to procure solar power from outside solar farms (either your own or run by others).

If you are keen to cut down your cost of power, solar may or may not be the solution, depending on what your current electricity rates are, the region you are located in. If your electricity rates (in cents/kWh or equivalent) are high and your region has plenty of sunshine, solar power might be able to provide some serious savings. Else, you may have to wait for a few years before it can.

If you are an investor keen on putting up solar power plants, now is as good a time as any to invest in solar, but don’t expect solar to provide you with quick returns – it is more for those looking for steady medium-long term returns.

If you are in the power sector keen on utilizing solar in your energy mix, rather than looking at solar as a silver bullet (and discovering it is not), utilize the potential of solar to shave peak generation costs, and its strengths as a distributed source to cut down transmission and distribution losses.

If you are already working in the solar energy sector, and are looking to promote solar energy adoption, prioritise your target segments – solar presents a much stronger business case for some market segments/demographics than the others, at least for the next 5 years.

If you are a government official looking at using solar as a key tool for social development, look at offgrid and distributed solar power as the key lever for significant value-add, rather than just large MW scale solar power plants which most times end up serving only those areas already having good grid connectivity.

If you are a student or working professional looking for exciting career options, solar energy is something you should really consider. It is one of the fastest growing industries, it has even better future growth potential, and most important – you can make a far bigger difference to the world working in solar energy than working in many other sectors.

And if you are someone keen on a datesolar can help you even. Seriously? Yes. All you need to do is to read this article many times over and pass it off as your own balanced view (and I wouldn’t mind, for Cupid’s sake) – what could impress that special someone better than your knowing stuff about one of hottest topics in the world today?

Thank you very much for reading my post. I will be glad to have your perspectives, counter points, questions and more. Do use the Comments section for this.

All the best!

Picture credit: The featured image is that of a heart shaped solar farm being built in New Caledonia in the South Pacific. Image Source: Payless Power