Solar roofing, as known as photovoltaic (PV) roofing, is a renewable energy technology that directly converts sunlight into electricity (DC type) based on the photoelectric effect in physics via solar cell modules as receiver/ converter. These days, this technology is no newcomer to Vietnamese households and businesses.
Considering the growing domestic demand for electricity while no new and rich power source is available, solar roofing is a prime solution that could reduce the pressure on electricity supply, give citizens the control over their daily activities, as well as save natural resources and protect the environment, effectively responding to climate change.
The solar roofing market in Vietnam
According to the statistics from Vietnam Electricity (EVN), by the end of September 2020, Vietnam has launched more than 33,000 solar roofing projects with a total installed capacity of 1,146 MWp. So far, over 55,000 solar roofing systems have gone into service with a total installed capacity of 1,531 MWp, generating 636.6 million kWh for the national electricity grid.
In the same period, the industry sector accounts for the largest proportion in Vietnam’s solar roofing structure of installation with 54.9%, equivalent to 840.5 MWp. Household ranked second with 484.5 MWp, accounting for 31.6% of the total installed capacity. The last two sectors are commerce and administration, respectively accounting for 9.9% and 3.6% of Vietnam’s solar roofing structure of installation.
Source: VIRAC, EVN
The Southern Power Corporation (EVNSPC) contributes the highest proportion (48.3%) of the total solar roofing installed capacity, equivalent to 739.21 MWp as of the end of September 2020. The region managed by Central Power Corporation (EVNCPC) has 544.26 MWp installed, equal to 35.5% of the nationwide installed capacity. The Northern Power Corporation (EVNNPC) accounts for a modest proportion of the total capacity, which is 5.5%.
Source: VIRAC, EVN
Vietnam’s solar roofing market: Conditions for prosperity
As a tropical country with a hot, humid climate and lots of sunshine, Vietnam has many advantages for developing rooftop solar power. South Vietnam dominates the national solar roofing market thanks to its natural blessing – a relatively high solar radiation intensity compared to the national average.
Besides, Vietnam has a valuable source of skilled and low-cost labour trusted by leading technology enterprises such as Intel, Samsung, Microsoft, and LG. The semiconductors industry also witnessed significant growth in the last few years, with the expected growth rate of 15% in 2020 according to data from TechNavio technology research and advisory company, which ensures the supply of a widely applied material in the production of batteries and other solar roofing equipment.
The Vietnamese government also creates a lot of momentum for developing renewable energy in general and rooftop solar power in particular through macro policies. Since 2017, numerous policies directly related to solar roofing have been introduced, providing a national development roadmap, project development guidelines, solar roofing purchasing contracts, pricing mechanism, etc.
Source: VIRAC General
On the other hand, these preferential policies and the decrease in investment costs thanks to new science and technology achievements have made the number of solar roofing projects increase in a massive and troublesome manner. Customers have been facing the risk of money loss or insecurity since numerous solar roofing businesses operate without a proper understanding of the national grid, quality assurance process, installation and warranty processes, etc.
Uscent 8.38/kWh (equivalent to 1,943 VND/kWh) is a favourable purchasing price that has been applied for solar roofing electricity since January 1st, 2020. However, it will be replaced after December 31st, causing understandable concerns for the customers-to-be.
Source: VIRAC General, EVN
The future of solar roofing
Half-cell solar panel
Vietnamese solar roofing’s great potential could not be fully unlocked unless domestic businesses actively update new trends and technologies. For example, half-cell solar panels with higher efficiency and more reliability than traditional ones are expected to flourish over the next ten years.
As the name can tell, half-cell batteries are twice as small as traditional batteries in size. Half-cell panels are photoelectric panels cut in half to improve performance and durability. Their current is also halved with this size, which lowers the resistance losses while generating more energy. Moreover, smaller cells perform better under mechanical stress, making them harder to crack.
Source: VIRAC, ITRPV
Solar roofing for public facilities
Around the world, public facilities such as garage, stadium, bus stations, etc. have been utilized for solar roofing, which helps reduce millions of tons of CO2 emissions as well as save space and other resources. In Vietnam, where customers’ awareness of environmental protection is growing fast, this application of solar roofing is expected to be adopted and widely applied in the near future.
In the future, temporary housing can be used for solar roofing as well. Scientists successfully created a photovoltaic fabric that can be used in both the textile and construction industries. Contemporary roofs such as canopies or tents are ideal for solar roofing since they are often exposed to a large amount of sunshine.
This solar fabric empowers temporary accommodations, such as awnings, to collect and store electricity. Permanent structures may also benefit from this since they often have retractable roof installed on the top floor or balcony. With solar fabric, applications of solar roofing are much further expanded.
Photovoltaic skin is a new invention that allows users to display customized images on solar panels exactly how they do that with their phone or laptop. This poses clear opportunities for businesses while also significantly benefits consumers. With photovoltaic skins, solar panels can be installed without ruining the house’s appearance.
At its core, photovoltaic skin is a thin layer of printable material that can transmit light. Consumers can rest assured that solar skin can beautify their roof without sacrifice efficiency. The balance between aesthetics and performance is the new ace for solar roofing to penetrate the market.
Solar glazing is made from solar cells that are so thin that they are almost transparent. Its applications are relatively similar to solar skins while also making photovoltaic windows possible. For solar roofing, this means new applications such as solar skylight that can let the light in and collect solar energy simultaneously.
This technology significantly enhances the flexibility of solar roofing, allowing homeowners to exploit solar energy more optimally. One disadvantage of solar glazing is that it is not as effective as other solar materials. Even so, given the steady 5% annual increase in electricity costs per year, every watt of electricity produced is precious.