Solar panels ought to be all the rage in sunny Singapore.
After all, there is no shortage of sunlight and the savings on electricity bill are sweet. Still, architects and building industry players say more needs to be done to entice local home owners to install them.
Mr Lim Hong Kian, director of designshop.architects, has incorporated solar panels into six houses over the last four years - compared to seven homes without them in the same time period.
"There is that initial capital outlay that puts off many home owners, even if you can make back the cost in a few years," says Mr Lim, 41.
But for those who want to do it for environmental reasons, he adds: "It's not a matter of budget anymore as it becomes really about conservation."
Dr Thomas Reindl, deputy chief executive officer of the Solar Energy Research Institute of Singapore, says there are three reasons most private home owners are not on board with getting a solar panel system: a lack of knowledge of how the panels would work on their buildings and within the electricity grid; uncertainty about what goes into putting a solar panel system in their house; and the grid utilisation charge, which is levied on every "green" electricity which is fed into the public grid.
He suggests looking at Germany as a good model of private homes adopting solar panels, as ordinary home owners get paid for the renewable electricity they generate.
"Germany has the largest installed capacity of solar power with 35GWp in total. Around half of that is private residential buildings. The main driver was that people not only enjoy 'green energy' but also make a reasonable return on investment over time. This is possible in Singapore too."
Aside from just private homes, Mr Lee Boon Woei, director of DP Sustainable Design, a subsidiary of DP Architects, says even as condominium developers have become more aware of the green cause in the last five years, it has "yet to see solar panels gain widespread usage".
Mr Lee, 44, says: "The technology of solar panels is still evolving, even though it is quite mature now, so it could be more efficient in the coming years. Developers might not want to lose out on returns so they opt to wait and see what's going to happen next."
The firm did a private residential home in Boon Teck Road in 2011, which featured solar panels. The three-storey inter-terrace house was the first private home to be given a Green Mark Platinum Award from the Building and Construction Authority.
But Mr Lee notes that solar hot-water systems, which heat up water for domestic usage, is more popular among residential developers. They differ from solar panels, or photovoltaic (PV) panels, which harvest solar energy and convert it to alternating current for electrical appliances. Solar hot- water systems absorb energy from the sun to heat water.
Last week, The Straits Times reported that more Singaporeans are using solar power to cut their bills and companies here which sell these panels are seeing more business. But the report added that it was still mainly commercial and industrial properties acquiring and using these panels.
Last November, supermarket giant Sheng Siong said it will kit out its distribution centre in Mandai with panels which will cover 11,000 sq m of the rooftop.
The Singapore Sports Hub, which is due to host its first events next month, has a 7,000 sq m rooftop installation, which will not only produce solar energy, but also act as a sunshade - two examples out of many others taking similar steps.
In comparison, Singapore-based Phoenix Solar, a company which sells solar panels, says in the eight years it has been around, it has installed its products in only about 30 homes.
But sustainability consultant Deepshi Bhogal at Pomeroy Studio says "solar technology is increasingly becoming an accepted part of a building's 'kit of parts'".
Her firm, Pomeroy Studio, is designing a 480 sq m house in Novena - designed by its United Kingdom-registered architect Jason Pomeroy - that will be completed next year and will have a PV output of about 18,360kWh a year. This will be enough to power a five-person household, with energy- efficient LED lighting, ceiling fans, receptacle and pump loads, which is estimated to use 8,130kWh a year. The balance can support the occasional use of an energy-efficient air-conditioning system.