enewable energy from the sun, wind and waves is set to become a key part of the global economy as it transitions towards a lower carbon energy future. Worldwide, Renewable Energy Network 21 (REN21) reported that the new renewable energy capacity installed established a new record of 2,017 GW in 2016 following an almost 9 per cent increase. Solar photovoltaic accounted for around 47 per cent of the capacity added, followed by wind power and hydropower.
“A global energy transition is well under way, with record new additions of installed renewable energy capacity, rapidly falling costs and the decoupling of economic growth and energy-related carbon dioxide emissions for the third year running,” said Arthouros Zervos, chair of REN21, a network of public and private sector groups covering 155 nations and 96 per cent of the world’s population.
In spite of the progress made, it is felt that the switch to green energy has to be speeded up if we are to counter the worst effects of climate change.
Singapore Goes for Solar
For tropical Singapore, solar presents the best option for electricity generation. Located one degree north of the equator, it has an average annual solar irradiance of 1,580 kilowatt hour per square metre, about 50 per cent more solar radiation than temperate countries.
The government has taken the lead in the adoption of solar photovoltaic systems for power generation. Under the SolarNova programme initiated by the Economic Development Board (EDB) in 2014, a Whole-of-Government approach was adopted to aggregate demand for solar photovoltaic across government agencies to achieve economies of scale and accelerate solar photovoltaic deployment.
With a million flats in 10,000 Housing and Development Board (HDB) blocks island-wide, the HDB is playing a key part in this programme. Its target is to install solar panels across 5,500 blocks by 2020, which will generate clean energy to power about 55,000 four-room flats every year. Solar panels on HDB blocks account for some 45 per cent of Singapore’s total solar installations, while non-residential installations in the private sector account for a further 46 per cent and residential homes less than 5 per cent.
By marshalling the rooftops, Singapore is able to overcome the limitations of land in a city measuring just 716.1 square kilometres.
Corporate giants have also signed up. In a landmark agreement with Sunseap in November 2015, Apple is running its entire Singapore operations with solar power. To fulfil the contract, Sunseap is drawing on the solar energy systems on rooftops across more than 800 buildings in its Singapore portfolio, including solar panels on HDB buildings in Jurong, Tampines, Sembawang and Marine Parade, as well as Apple’s own Yio Chu Kang office, to supply up to 40 gigawatt hours of energy to Apple.
Sunseap co-founder and director Frank Phuan says: “The Apple project has laid the groundwork for further solar development in Singapore and the region in many ways. Previously in Singapore, the only way to adopt clean energy was to install a photovoltaic system to generate solar energy. However, limitations in space restrict large-scale adoption.”
This has put Singapore on track to exceed the 3,501 megawatt peak (MWp) target by 2020 and more than one gigawatt peak after that, which would represent about 15 per cent of electrical power demand at peak during the day. According to the Energy Market Authority (EMA), Singapore’s energy regulator, installation of solar panels has quadrupled from 33.1 MWp in 2014 to 129.8 MWp in 2017. Peak power refers to the output achieved by a solar module under full solar radiation.
The outlook is bright as cost, once a deterrent to adoption, is becoming less of an issue with technological improvements. More leasing options are also being made available and the EMA is making it easier for consumers to be paid for supplying to the grid the excess energy they generate.
Qualitative Improvements Through Research
Singapore is boosting its ability to forecast solar energy output through a S$6.2 million research grant awarded to a consortium led by the National University of Singapore. The consortium is working with the EMA and the Meteorological Service Singapore (MET) to develop a forecasting model. The model will help to improve management of fluctuations in solar output to ensure grid reliability.
Local weather conditions are marked by humidity and intense cloud cover on rainy days, which can cause a significant drop in the amount of solar energy generated. Fluctuations, “if not properly accounted for… may lead to imbalances between electricity demand and supply, especially when solar energy becomes a larger part of the fuel mix,” said an EMA spokesperson.
The researchers will look at improving the accuracy of solar photovoltaic output forecasts and grid management by using techniques in weather prediction and remote sensing, among other things. They will also use data from sensors installed on rooftops and those installed by the MET.