An engineer’s view... Solar energy - Best source of Domestic Energy

Engineer G.G.N. Gunawardhana speaks about the economic viability of using solar energy in a country like Sri Lanka where sunlight is abundant. He says it is a viable option for domestic energy requirements. He shared the following with The Daily Mirror:

 Q  How do you describe the suitability of solar energy for a tropical country like Sri Lanka?  

Solar Panels should be the main source of energy in countries like Sri Lanka as we have abundant sunlight throughout the year. We have sunlight for more than 12 hours a day; 365 days a year. As a region that goes through four seasons,Europe has more watts per capita than Sri Lanka, which is saddening as we have plenty of sunlight throughout the year though we are far behind.  
Sri Lanka has had power cuts throughout the past few years due to lack of rain which results in the reduction of hydro-power energy. So during droughts our country has to over rely on fossil fuels to produce energy to help run our country and during the last few years it is evident that Sri Lanka does not have the capacity to solely rely on fossil fuels to power our country. This is why I feel we have still not used solar power effectively, and if the general public uses solar power in their households, we will not have to rely on fossil fuels as we do in the present. And also, it would reduce a lot of our cash being spent on fuel which has to be bought to run the diesel power plants. So, as you can see a tropical country like ours, especially considering the problematic situation we are in when it comes to over reliance on fossil fuels during droughts, it would probably be the ideal country for solar power.  
I personally believe having solar panels in Sri Lanka will improve the standard of life in most households, because most people refrain from buying air conditioners to avoid paying high electricity bills every month. But if you have solar power this will not worry you. You will be able to have an air conditioner without having to think about a 5-digit electricity bill every month. 

  Q   The government wants to go for renewable energy for a bulk of its energy requirement. What is your comment in this regard?

It is commendable that the Government wants to take initiative to make solar energy for the bulk of its energy requirement. If this matter was taken seriously, we would experience power cuts today.  
As I mentioned earlier a country like ours that has sunlight throughout the year is ideal for solar power. It is humorous as to why, as Sri Lankans, we have not considered making solar energy for the bulk of the energy requirement earlier, unlike diesel or coal, Sunlight is totally “free”.  
Yes, there is an initial cost which we will have to bear when setting up a system, but it is important to keep in mind that once the initial investment is done we can reap the benefits of it for the next 25-30 years. Or in other words if you set up a solar energy system for the next 25-30 years you will not have to pay for electricity at all.  
This is applicable to both the government and to individuals of our country. The government will spend less on Diesel and coal in the long term and also the individuals who mount solar panels on their roofs will not have to pay money on Electricity in their foreseeable future.  
On another point of view, renewable energy is free of any carbon emissions. I believe as Sri Lankans,it is our duty and responsibility to make sure we save our Planet for our younger generations. And if we take the current pandemic into account, it has taught us that health is the most important aspect for any human and we should do our best to reduce our carbon footprint.  

 Q  How do you define international trends as far as solar energy is concerned?

A lot of countries consider solar energy as a sustainable resource of energy which most importantly can be easily accessed by the general public. Due to the ease of access to solar energy many governments see solar energy as an opportunity to move away from coal or diesel power plants. In order to encourage the general public into setting up solar panels in their roof’s most governments offer their citizens incentives such as zero interest loans, tax concessions and even subsidizing a certain amount from the initial cost of setting up a solar panel system.  
One of the emerging trends as far as solar energy is concerned is the integration of solar energy into modern city development. Many cities see solar energy as a way to make sure the new cities are self-sufficient in electricity and that these cities emit the least amount of carbon emissions. Another trend in Solar energy is that the cost has dropped and is still dropping drastically. This is a result of many companies especially in China getting into the market with their products which are cheaper than its competitors. This has led to other manufacturers dropping their price as well as the result of which, solar panels and inverters became cheapest than it has ever been. This is another major reason for cities to see Solar energy as a viable source of renewable energy.  

 Q   Technologically how competent are we in developing solar energy?

In my opinion, if the government can manufacture solar panels and inverters locally and promote it to every household for a cheaper, affordable price, it would be an integrated solution rather than importing. Also, solar electricity production should be optimised to cover the day-time electricity requirement only. Because solar electricity will only be available during the daytime and if we are to use the same energy in the nights, we require battery storage which is expensive, and it is not a very feasible option. Another option to store electricity is by hydro power. During the day-time, water can be pumped to a higher level and in the nights and be allowed to flow free and power could be generated using hydro-power.  
If we do not come up with a solution to store solar electricity during night-time, the concept of green energy is lost because we have to depend on generators at night. The other problem of running a generator is that it affects our country’s economy as we have to import fuel. Further if we could promote electric cars, fuel can be replaced with electricity, which is powered by our self-produced green energy.  

 Q  For an ordinary person to install a rooftop solar panel will be very expensive. How can it be addressed?    

I believe the solution is already being brought up by the government. But majority of the people are not aware of it. Loans are given to purchase solar panels at very low interest rates by several banks. But the salesmen with lack of knowledge in this industry is the reason behind the unpopularity of solar energy. It is a challenging task to explain and make a client understand the background and benefit of using this system.  
For example, when a person installs a solar energy system through a bank loan, he will no longer have to pay for electricity and his monthly installment for the loan, which is lesser than the monthly electricity bill. Also, if the client wants to, he can claim money from the CEB for the extra electricity that his solar energy system produces, which will help him pay off to his installment plan. Customizing these ideas and prompting this to clients depending on their energy consumption and financial background requires both technical and marketing skills.  

 Q  How effective is solar generation during days with less sunlight such as rainy days?    

Production rate will drop by at least 20% during rainy months. To overcome this issue we recommend the clients to install a solar system which is 10% higher than their actual production because in months like February, March, April, May and June the production is comparatively higher hence, the clients have the option to bank the excess electricity and use it during the rainy season when the solar harvesting is less.