Technology | Electrification | Solar

Rooftop solar: a sustainable energy source we still overlook

Why overlooking rooftop solar is pricey oversight

Published Nov, 2023

It started our solar system, keeps our planet in a stable orbit, dictates the weather, photosynthesises our food, lifts our mood, and can power our homes. We are far more dependent on our sun than we spend time reflecting on. Every 90 minutes or so, we receive enough energy from the sun that if converted efficiently can power our entire economy for a year.

Yet many still ask, what is solar energy? Put simply, it is energy converted from sunlight into two of our most widely used forms of energy - electricity and heat.

Of all the sustainable electricity sources out there, solar represents the most accessible form that almost anyone can set up these days. There are billions of buildings across the world with the infrastructure partly in place to host a rooftop solar panel. We understand the science around solar energy and have billions of roofs most ready to host a rooftop solar system. Yet the use of rooftop solar is dismally low across the world.

Here's why continuing to overlook this sustainable energy solution is a pricey oversight.

We have the roofs to host it already

One of the most intriguing aspects of the future of rooftop solar is that we already have the infrastructure to make it global in place. Billions of rooftops across the planet are already generally structurally fit for rooftop solar, and they all point upwards in the direction of the sun.

Of course, structural fitness of rooftops, local sunlight intensity, weather/climate, electricity cost, installation cost are all factors contributing to the cost-effectiveness of rooftop solar. All of these are, however, addressable factors if we truly value the impact of our current electricity generation processes on the environment.

It is more affordable than ever

The confluence of technology, demand and sustainable energy awareness has contributed to the dramatic fall in the cost of solar PV equipment and installation. Analysts at the IEA put the fall in prices at over 80% in the course of the last decade.

Whilst the actual cost of equipment and installation has fallen dramatically, the economic value of using solar instead of conventional electricity feeds hasn't fared so well. This is yet another case of the status quo getting in the way of a better future. The amount of money and time we have spent and continue to spend on conventional grid electricity outstrips what is currently spent on solar.

Although the benefits of rooftop solar (for domestic use) trumps conventional electricity in the long run, most homeowners are focused on the short term—transitioning from grid electricity to solar has a steep upfront cost. Government policymaking teams that should know better tend to be filled with people with short-term career goals rather than the long-term benefit to society and environment.

With significantly lower costs of equipment and installation, a fully understood technology that taps into an inexhaustible source of energy and rooftop infrastructures that are already in place above our homes; the continued slow uptake of rooftop solar is rather perplexing.

No technical limitations exist for rooftop solar

In its 2020 technical report on the state of rooftop solar deployment, the IEA concluded that "in general, barriers are social, financial, psychological, and regulatory rather than technical. The technology has reached such a level of maturity that it can be deployed easily everywhere." .

For new developments in sunny California, USA or Sydney, Australia to still be built without rooftop solar as standard given all we know today is really thought-provoking for people who know the challenges that climate change constitutes and the role that shifting our domestic energy use can play in our transition to sustainable energy sourcing. Although it must be noted that Australia already ranks among the highest PV capacity installed per inhabitant, and for a brief period in the spring of 2023, the southern state of South Australia generated enough power to meet its total energy needs from rooftop solar panels alone.But failing to integrate solar PV into every new roof is a missed opportunity at advancing the country's contribution to the world's transition towards sustainable energy sourcing.

Addressing climate change will require various countries to chip in what their geography, economy, culture and other distinguishing factors allow them to contribute to. Australia is hot and wealthy, it should be a world leader in the deployment of rooftop solar among other things it already contributes.

The technical aspects of transitioning households from grid electricity to stand-alone rooftop solar arrays should have at this stage been resolved completely. We have many case studies to learn from and a plethora of experts in the field, all of who have better access to information and technology.

Yet we are stuck with questions like—can a house rely entirely on solar power? Yes it can. By installing rooftop solar cells capable of producing more energy than the household consumes. The addition of optional battery packs can smooth-out variations in the production capacity of solar cells.

Battery is a game changer

One of rooftop solar’s Achilles heels is the intermittent nature of its energy supply. Our energy use profile does not necessarily line up with the weather. We need power on both sunny and cloudy days, yet rooftop solar doesn't really do cloudy days. That is where batteries come in. Pairing rooftop solar with batteries helps smooth out the problem associated with the intermittency of rooftop solar energy generation.

This pairing has been used extensively on an industrial scale, and it is a technology that can be scaled down for domestic use. There is no harm in adapting our lives to variable energy levels anyway. Coping with intermittency is a natural adaptation that we seem to have lost to our desire to have it all, all the time. Critical systems aside, learning to control our use of electricity is a lesson that solar plus batteries can teach us.

Supply chain ethical and national security issues are surmountable

The issues surrounding the sourcing of materials for solar cells is a disturbing one that rears its ugly head in many conversations about rooftop solar. The domination of the solar PV cells market by few countries is used as a reason against widespread adoption of rooftop solar. The truth is that this didn't stop us importing our electronics and white goods from a single country for decades. Have we really just woken up to this problem or is it just a convenient argument?

Child labour, human exploitation, ethnic and racial discrimination are all things that we abhor and we should refrain from actions that can exacerbate the suffering of people in those conditions. That must include not doing business with countries that don't seem to share those core human beliefs.

But the business of supply chain management is one that we understand quite well. To varying levels of success, the world has managed these sorts of issues from tackling the scourge of blood diamonds to the fair trade movement.

Apple sells millions of phones and computers every year - all produced in a handful of countries under intense supply chain scrutiny from Apple. The Apple model shows that when we really care, we can manage supply chains in a manner consistent with the values we hold dear.

The issues surrounding the manufacture and supply of solar PV cells are surmountable and are therefore a lame excuse against the pushing for the widespread adoption of rooftop solar.

Things you can do today

Start a conversation with your elected representatives on their views and support for policies on rooftop solar. Remember, if government policy mandates it, corporations will produce it and you have the power to shape government policy through these discussions with your elected representatives. They represent you. They want your vote. Talk to them.

Also speak to them about commissioning expert studies into what it will take for all households in entire towns to have rooftop solar. Your tax money goes to universities studying how to tackle all sorts of problems, why is this not a prominent issue for them? We are so close yet so far from the solution.

Review your ability to switch to solar energy today. For those living in houses, see how many homes in your area have rooftop solar installed. For apartment dwellers, check if you can switch your energy supplier to those using sustainable energy sources.