By Szu-Hsin Wu
Green innovation can be found in various forms, such as renewable energy, electronic vehicles, shower timer. Green product innovation focuses on modifying product design by using nontoxic or biodegradable materials in order to reduce the disposal impact on the environment. In other words, green product innovation is intended to improve the durability and recyclability of products. Green process innovation aims to improve energy and resource efficiency during the production process or create the process which converts waste into valuable resources for other production. In particular, green process innovation is also featured in reducing air or water emissions and switching from fossils fuels to green energy. Dŵr Uisce is working on developing innovative solutions to improve the efficiency of water distribution networks in Ireland and Wales. Developing a viable and environmentally sustainable response to customers’ demands has been a critical challenge. We actively collaborate with key stakeholders and consider the commercial potential and the environmental and ecological impact while addressing the challenge.
The applicability of micro-hydropower systems in water networks to recover energy has been recognised for years. In response, the Dŵr Uisce project stakeholders co-developed a system based upon a pump-as-turbine (PAT). Pumps are adapted in reverse to produce rather than consume energy. Pumps are mass-produced and available off-the-shelf in different sizes and types. Using PAT as an essential component of the energy recovery system, the costs are up to 15 times less expensive than conventional hydropower turbines. To date, Dŵr Uisce has implemented micro-hydropower energy recovery system developed from conceptualisation and laboratory tests to full-scale installations at two demonstration sites: Blackstairs Group Water Scheme (Wexford, Ireland) and Tŷ Mawr Wybrnant (Wales, United Kingdom). With the implementation of these systems, the environmental impact is assessed in terms of the potential CO2 emissions saving, assessment of negative ecological impacts, impacts on affordability of water supply.
The implementation at Blackstairs Group Water Scheme is a gravity-fed system supplied by the main reservoir located on the east face of Blackstairs Mountain, Co. Wexford. The reservoir provides drinking water to 1037 local households with an overall average demand of 1500 m3/day. The distribution system has an approximate total length of 117 km of pipework with diameters ranging from 50 to 150 mm. The water treatment works are operated by an external water service company.
The initial purpose of the project for Blackstairs Group Water Scheme was practical and focussed on efficiency. The resulting micro-hydropower energy recovery system now generates electricity, reducing the energy consumption of the treatment works by 20-25% and promising a return on investment of 4-6 years, depending on water consumption rates and rainfall. The CO2eq emission savings of this installation are equal to 16.2 tonnes per year. The economic savings from this project, rather than being distributed among the members, was donated to a water project in Uganda, Wells of Life Ireland.
Tŷ Mawr Wybrnant is a historical site in North Wales, owned and managed by National Trust Wales. The site features a 16th century historical farmhouse and a rare collection of Bibles. It was also the birthplace of Bishop William Morgan who is the first translator of the Bible into Welsh. This culturally important book and over 200 other bibles in different languages are on show at the property but susceptible to moisture in the air. Further, climate change with increasingly heavy and persistent rainfall, flooding and damp have put the collection at risk. At Tŷ Mawr Wybrnant, the Dŵr Uisce project stakeholders co-designed and installed a prototype micro-hydropower energy recovery system to generate electricity from a nearby stream, technically similar to the system at BGWS. It differs functionally, providing heat and light to the adjacent historical building which is now “off-grid”. The CO2eq emission savings of this installation are equal to 5.3 tonnes per year. The system at Tŷ Mawr Wybrnant was to be used to dehumidify the historic property and to protect the collection of rare books.
Figure 2 Micro-hydropower energy recovery system at Tŷ Mawr Wybrnant
Blackstairs Group Water Scheme could have distributed the cost-saving to the local community. Instead, the saving was donated to a water charity drilling wells – Wells of Life Ireland, in Uganda. Similarly, Tŷ Mawr Wybrnant used the electricity generated to control humidity levels in the building. However, they evaluated the impact in terms of protecting national heritage, including a priceless collection of Bibles curated in the building. These social missions were not evident at the outset of the innovation initiatives. The implementation of green process innovation at both sites is transformed into social impacts to the global society. These social impacts are unexpected but have led to truly sustainable water innovation.