In the ancient Mediterranean, there was a famous city called Syracuse. Legend has it that when the Roman ships were attacking the place in 212 BC, one of the most gifted children of the city, named Archimedes, decided to take on the Romans-- not by sword but in the mind game.
Archimedes-- a scientific genius who later became famous for his 'Eureka' story, allegedly arranged a group of soldiers who would held flat plate mirrors in an almost hemispherical position to form a large concave mirror.
This 'burning glass of Archimides' which allegedly composed of 24 mirrors, conveyed the rays of the sun into a common focus and produced an extraordinary degree of heat which set fire to Roman ships.
While it is a tragedy that one of the first cases of solar energy application remains tied with warfare, the story also serves as a reminder that when used in an intelligent manner, the power of the sun (or any natural force for that matter) has the potential of doing the impossible.
For the most part of its history, human civilization has been dependent largely on renewable energy sources. It is only during the 19th century that non renewable sources became predominant.
However, now with the growing global concern that all nonrenewable sources have limited reserve and can have detrimental effect on the environment, human society is now once again looking back to the eternal forces of Mother Nature -- sun, wind or water to meet their energy demand.
According to the latest report of global energy think tank REN21, renewable energy comprised 19.3 percent of total global energy consumption back in 2015, with much of the growth coming from the developing world.
Bangladesh, with more than 4 million units of Solar Home System, has been termed as the largest SHS market worldwide by the same report.
Bangladesh's success with SHS actually proves a point about the prospect of renewable energy or more specifically solar energy in the country.
Despite the country's recent success in increasing power generation capacity, almost 40 million people are deprived of electricity. While energy demand is increasing day by day with rapid urbanisation, mechanisation and industrialisation, supply remains largely dependent on the declining domestic reserve and import.
The country's urban and rural areas alike are also becoming highly vulnerable to growing air, water and soil pollution due to over dependence and inefficient use of such conventional fossil fuels.
Such a situation calls for increased exploration of alternative energy sources including sources that are clean and renewable. Renewable energy currently constitutes only 2.89 per cent of the country's electricity generation mix. However, the government's Renewable Energy Policy obligates the share of renewable energy to be 10 per cent by 2020.
Among all forms of renewable energy sources-- solar energy apparently has the brightest prospect in Bangladesh. The country's tropical climate allows it to receive adequate sunshine throughout the year, which makes it an ideal breeding ground for solar powered schemes. The country's success with Solar Home Systems already acts a test case in this regard. Going forward, however, the key in tapping further potentials of solar energy will be to explore new avenues of utilising this resource.
Currently, only 216.75 MW of electricity in the country comes from solar energy sources, which is 48.1 per cent of the total renewable energy generation capacity of the country. Notably, the figure is still outnumbered by hydro power which has a generation capacity of 230 MW.
The government, however, has already set a target of increasing the renewable energy generation capacity to 2896.68 MW by 2021, more than half of which (1470 MW) is expected to come from solar power by that time. This means that the country has to increase its generation capacity of solar power by almost seven times in next four years.
Wind power, which is currently at an experimental stage, is expected to contribute 1153 MW by the same time period. The contribution of hydro power, on the other hand, would remain static at 236 MW during the same period.
This means that solar and wind energy-- and more particularly solar energy schemes need to follow a robust and dynamic growth pattern in the coming years to materialise the country's renewable energy goals.
The government has already identified or piloted some potential schemes where there are immense scopes for experimenting with renewable energy. Solar park, solar mini grid, solar irrigation, solar powered boating system, solar rooftop system and commercial solar charging stations are the few piloted initiatives which are likely to become success stories in the coming years.
The first step in large scale community based usage of solar power is solar mini grids. The advantage of a solar mini-grid is that it can meet higher energy demands and can boost business activities in rural areas. According to SREDA, a total of 11 solar mini grids with a cumulative capacity of 2.19 MW has been installed in the country while 15 more such projects are under implementation with a cumulative capacity of 3.17 MW.
Infrastructure Development Company Limited (IDCOL), which is a pioneer in financing the SHS revolution in the country, has already installed 9 such projects while 20 more are in the pipeline. IDCOl has a target of financing 50 such projects by 2018 and 500 of the same by 2025.
Apart from reaching the off-grid population in remote areas, solar energy also has the potentials to contribute to the national grid in the form of grid-tied solar parks. It is notable that the government has recently signed four Power Purchasing Agreements with various firms to set up solar parks which is likely to be operational within 18 months and are expected to add 302 MW of electricity. In addition, Letter of Intents (LoIs) have been signed with some more firms which are expected to add 528 MWs to the national grids when they come into operation.
However, as solar parks usually require substantial amounts of space, acquiring the required land for setting up such parks remain a major concern. According to experts, it requires 3 acres of land for a solar park to generate 1 MW of electricity. This can be a headache for a land hungry country like Bangladesh. However, there is ample unutilised government owned land including the unused land owned by the railway department that can be effectively utilized for the development of solar parks.
The government has a target to replace these diesel operated pumps by solar irrigation systems.
As per the records of SREDA, a total of 771 solar irrigation systems are in operation in the country. However, the target is to bring this number to one hundred thousand by 2025 which sounds ambitious but realistic. Nevertheless, it is notable that given the nature of agricultural activities in our country, actual irrigation works are required for only three to four months of a year. This means that thousands of solar irrigation systems are likely to remain idle for the rest of the year. New techniques should be evolved to use these solar pumps for some other purposes within the agricultural cycle so that they can be used year-round.
The government has set a target of increasing the wind power generation capacity to 1153 MW by 2021. However, this seems a bit ambitious as the usage of wind energy in Bangladesh is still at an experimental stage. However, the coastal areas and some border areas of the country which receive relatively strong wind flow may have some potential in this regard. SREDA has taken the initiative to carry out wind resource mapping in nine areas of the country. The report of this study is expected to come out next year and is likely to shed some light on the potentials of wind energy in the country.
One of the biggest technical concerns when it comes to solar energy is the issue of efficiency. Currently, the average solar cells available in the market have an efficiency level of 17 per cent. Researches are being carried out globally to increase the efficiency level of solar cells. Recently, it has been reported that researchers in Japan had set a new record for the efficiency of mass-produced solar panels, bringing the efficiency level of their solar panels to 26 per cent.
Since, renewable energy is an emerging arena, a lot of new research and development is taking place within this field globally. The government, therefore, should encourage and incentivize further knowledge sharing and technology transfer from the outside world when it comes to renewable energy including solar energy. Incentives should also be given for the domestic manufacturing of solar panels or for the importing of relevant parts and equipment.
It is also notable that currently conventional banks are not much interested in financing renewable energy initiatives. According to the latest figures of Bangladesh Bank, a total of Tk. 12149.52 million was channelled in direct green financing activities by the banks during the first quarter of this year. Only 4.77 per cent of this amount was made available to renewable energy.
Apparently, there is a lack of incentive for the banks in financing renewable energy or any green banking schemes. To address this situation, the central bank can introduce the system of rating and awarding based on the banks' involvement in green financing. There can also be preferential access to funds for banks that would channel a substantial amount of their loans into green banking. Central bank should also effectively monitor whether the banks are actively complying with the relevant regulatory provisions in this regard.
The impact of an increased renewable energy generation capacity can be manifold on a country like Bangladesh. Renewable energy sources, especially solar power, can help decrease its dependency on imported fossil fuels and reduce the pressure on grid electricity.