Darco: Automated Garbage Disposal Systems That Keep Our HDB Estates Clean and Green

Darco Water Technologies Limited (“Darco”) (SGX Stock Symbol BLR.SI) is well-known as a provider of integrated engineering and knowledge-based water and wastewater treatment solutions. But it is also a provider of automated centralised solid waste collection and disposal solutions. Known as centralised pneumatic/vacuum systems (“PV systems)’ they use a combination of vacuum sucking and compressed air pushing to collect and transport the solid waste.

The collection and disposal of solid waste (more commonly known as garbage or trash) is an issue that every city in the world has to grapple with. For many decades this was a mainly manual labour-intensive, dirty, and pollutive business. Collection centres are smelly and swarm with flies. Fuel-guzzling garbage trucks emit pollutive fumes and spill their leakage on the road. However, technology has caught up with the industry, and ‘smart’ cities now have mechanised and automated garbage collection and disposal systems. Darco has installed and maintained PV systems in HDB estates like Punggol and Tengah.

In this article, we showcase Darco’s PV systems projects; explain how they work, why from the perspective of ESG they are the future of waste management, and the business potential for such systems.

How do centralized vacuum systems for solid waste management work?

PV systems are designed to collect solid waste and transport it through a network of underground pipes to a central location for processing and disposal.

Here's how it works:

  1. Waste is collected from individual homes, buildings, or public spaces into collection points, usually located within a short walking distance. These collection points typically consist of a set of inlets that are embedded into the ground, along with a storage bin for the waste.
  2. Waste is deposited into the inlets by residents or building maintenance personnel.
  3. Once the inlets are full, the waste is sucked into the central vacuum system through a network of underground pipes, using a powerful vacuum pump.
  4. The waste is then pushed and transported through the pipes by pneumatic compressed air to a central collection station or waste management facility, where it is sorted, treated, and disposed of according to local regulations.
  5. The vacuum system is equipped with sensors and control devices to ensure efficient operation and prevent blockages or overflows.

Overall, central vacuum systems for solid waste disposal can improve the cleanliness and hygiene of cities, reduce noise and pollution from garbage trucks, and increase the efficiency of waste management. However, they also require significant upfront investment and ongoing maintenance, and may not be suitable for all types of urban environments.

Which cities in the world have centralised vacuum systems for solid waste disposal?

Centralized vacuum systems for solid waste disposal are still a relatively new technology, and as of 2021, they are only implemented in a few cities around the world. Some of the cities that have adopted pneumatic waste collection systems include:

  1. Stockholm, Sweden
  2. Barcelona, Spain
  3. Singapore
  4. Oslo, Norway
  5. New Songdo City, South Korea
  6. Beijing, China (in some new residential areas)
  7. Dubai, UAE (in some new residential areas)

This technology is usually to parts of a city rather than the whole city, as the infrastructure (which is mainly underground) has to be laid at the planning stage. Therefore, PV systems are often implemented in residential or commercial developments. However, as PV systems are more cost-effective in the long run, some cities may choose to switch to PV systems despite the initial cost of ‘digging up the ground’ to lay the infrastructure.

What are the Singapore government's plans for centralised vacuum solid waste disposal systems in the new public housing estates?

The Singapore government had already introduced centralized vacuum solid waste disposal systems in some new public housing estates, such as Punggol Northshore Estate and Tengah Estate. These estates were developed under the Housing & Development Board's (HDB) Design, Build, and Sell Scheme (DBSS) and included a range of sustainable features, including PV systems.

In fact, the Singapore government has been actively promoting the adoption of PV systems in both public and private developments as part of its efforts to improve waste management and promote sustainable living. PV systems are regarded as a Green product. In 2020, the National Environment Agency (NEA) announced that it would be providing funding support to public sector agencies and private developers who adopt such systems. As an example, Changi Airport Terminal 3 was built to incorporate PV systems.

Overall, Singapore's government has been proactive in adopting sustainable solutions for waste management, and the introduction of PV systems in public housing estates is just one of the many initiatives aimed at achieving this goal.


Why are pneumatic solid waste disposal systems more environmentally sustainable?

PV systems are generally considered more environmentally sustainable than traditional waste collection and disposal methods for several reasons:

  1. Reduced carbon emissions: With pneumatic systems, waste is transported through a network of underground pipes using a vacuum system, which eliminates the need for collection trucks and their associated carbon emissions. This results in a significant reduction in greenhouse gas emissions and other pollutants that contribute to climate change.
  2. Increased recycling: In many cases, pneumatic systems are designed to encourage waste separation and recycling by providing separate inlets for different types of waste. This can help reduce the amount of waste sent to landfills and promote the use of recycled materials.
  3. Improved hygiene and sanitation: Pneumatic systems reduce the risk of pests, odours, and other problems commonly associated with traditional waste collection and disposal methods, which can improve public health and hygiene.
  4. Space-saving: Pneumatic systems require less space than traditional waste collection methods, as they do not require large storage areas for waste bins or trucks. The problems of leakage and foul odours in the neighborhood are also eliminated
  5. Lower operational costs: While the initial installation cost of a pneumatic system may be higher than traditional waste collection methods, the operating costs are typically lower over the long term. This is because pneumatic systems require less labour, fuel, and maintenance, and can be operated more efficiently.

Overall, pneumatic solid waste disposal systems offer a more sustainable and efficient solution for managing waste in urban environments, helping to reduce the environmental impact of waste collection and disposal.

Business potential

  • Savings in labour costs and reliance on foreign labour (for Singapore)
  • Transportation costs to the landfill are saved
  • Higher recycling rate due to sorting
  • Installation usually comes with a long-term maintenance contract (as long as 10 years)
  • Retrofitting of old estates with PV systems is possible.
  • Infrastructure can coexist alongside ‘old’ manual systems
  • High initial cost but long term-savings
  • A quantifiable initiative in an era of ESG accountability
  • An attractive option for high-end property developers to attract buyers
  • Knowledge-integrated engineered systems such as those by Darco that can be customised to client requirements can be ‘exported’ to cities in the region

For original article, please visit: Darco: Automated Garbage Disposal Systems That Keep Our HDB Estates Clean and Green- Investor-One