Unlocking additional hydropower5 August 2021
Unlocking additional sustainable, reliable hydropower generation – both from the existing fleet and from new project development – are at the heart of Natel Energy’s developments. IWP&DC spoke to CEO Gia Schneider to find out more about the company and its product offerings
At the end of last year, Natel Energy – a supplier of sustainable hydropower solutions – announced the successful completion of the Monroe Hydro Project in Oregon, US, with the installation of its 1MW class D190 Restoration Hydro Turbine (RHT), and 100% safe fish passage test results from the Pacific Northwest National Laboratory (PNNL).
The project, which is a first-of-its-kind design making use of an existing irrigation canal and a new fish safe turbine technology to generate reliable, renewable energy, was the second commercial installation of the company’s Restoration Hydro Turbines.
The RHT is a compact propeller-style turbine with specially designed blades that allow large fish to pass safely. In September 2020, PNNL conducted turbine passage tests that revealed a 100% survival rate for rainbow trout up to 400mm (15 inches) long passing downstream through the 1.9m diameter D190 RHT. Over the course of testing, the gross head at the site was approximately 5.2 meters, and the turbine produced approximately 300 kW electrical output. With the support of the WPTO, PNNL scientists and engineers used Sensor Fish, RFID tag, radio tag, and balloon tag technologies to assess physical turbine stressors and enable the recovery of all fish after their passage through the turbine. Each fish was carefully inspected after passing through the turbine, and no evidence of passage related injuries was observed. This is surprisingly good performance given the compactness of the turbine relative to the large size of fish tested – and at less than 2m in diameter, the RHT is the most compact turbine that has demonstrated this successful survival rate for large fish.
The RHT was conceived in late 2018, and Natel Energy CEO Gia Schneider explained that the concept went very quickly from idea through to 100kW prototype scale testing in about five or six months.
“We did our first fish passage test within about seven months and we had our first project installed within a year,” Schneider explained. “By the end of 2019 we had our first project installed in Maine. This was quite a small project as our initial first installation. That project has been running for a year and a half, and has been operating at 97-98% availability. It has met all its generation expectations – which is what you hope from a first deployment and a commercial product.
“We then installed the second project in 2020 – at the height of the Coronavirus Pandemic – in Oregon. That project has now been online and operating successfully for about 10 months or so. We were very fortunate that everything worked out during this installation – we didn’t end up with any big supplier delays, shipping delays or construction delays as a result of Covid-19. We were largely able to hit our construction schedule.”
Benefits of the turbine
Designed with a 25-year operating life, the RHT requires no fine fish screens and minimizes the need for excavation and installation materials, reducing the overall cost to install. In addition, the RHT features a variable-speed direct-drive permanent magnet generator, delivering high efficiency across a wide range of flow rates on a simple and reliable powertrain.
“The turbine itself is a compact modular unit that is less expensive to install, particularly for arrays,” explained Schneider. “The offset is that you could either do a large diameter Kaplan unit or you could do an array of our units. When you stack up the civil works costs and the total package we are able to reduce excavation and concrete costs, meaning we’re less expensive on the turbine package.
“In jurisdictions where fish passage is important, we can offer the ability to install our units without fish screens. That’s a big cost saving. The turbine is very robust to debris – it passes fish safely but it also passes debris safety. In low head situations where you might find a lot of travelling sediment, leaves etc, this aspect helps moderate the ongoing O&M costs.”
The RHT is suitable for upgrading or repowering existing small hydro plants with modern, high-performance fish safe turbines; for adding new generation to existing non-power dams; and for new hydro development.
Another area the company is looking at is the possibility of removing existing dams and replacing them with a new restoration hydro project to restore connectivity, undertake some river restoration, and at the same time add hydropower.
“We need to invest in our water infrastructure and what has have been focused on is creating a pathway for that investment in our infrastructure, a pathway that is both supported by the environmental community because it is helping to deliver river restoration outcomes but at the same time is generating new reliable renewable energy,” commented Schneider. “Every hydro project is a water project and when we think about all the issues we face around water in both developed and developing countries, we are going to need to invest in a lot of water infrastructure to manage it, but that investment is going to look quite different to the old approach because we have more constraints that we are balancing against, in particular around environmental outcomes.
“Restoration Hydro combines best practices from stream restoration, whitewater recreation, and even dam removals, with modern low-head hydropower technology to create a blueprint for a new generation of water-power-restoration projects. In addition to producing reliable, renewable energy, Restoration Hydro projects generate multiple environmental co-benefits that may include habitat creation, improved water quality, and sustained increases in groundwater and aquifer recharge rates. When deployed strategically at multiple sites across a basin, Restoration Hydro projects enhance river, wetland and watershed connectivity, which can help mitigate the impacts of droughts and floods.”
Natel Energy’s product offering goes up to about a 2.5MW for individual units currently, but Gia Schneider explained that the company’s model is to deploy multiple modular units. The projects the company is currently focused on are generally between 1MW and 25MW.
The company will be carrying out its first installation in Central Europe later this year, and is also looking at installations in Africa in early 2022. Schneider added that the company is interested and open to partnerships.
“It’s something we are thinking about in regards to different geographies,” she said. “At the end of the day our patents are specific to the shape of the runner of the turbine blades. The rest of the turbine package varies – we have a pit configuration, bulb configuration, and irregular inflow. These are all common configurations in hydro turbines generally - therefore partnership is something we think is a very natural path for us.”
Natel Energy is currently working on several other product/service offerings through its software subsidiary, Upstream Tech. One such service is HydroForecast, which combines satellite imagery, machine learning, hydrologic science and weather data to provide a more accurate forecast of streamflow, both over the near term and seasonally. The company is selling that product directly to several hydropower utilities in the US and Europe, and it’s something that can be bundled with turbines on new projects to help provide better data for operational optimisation.
Another area the company is working on is the ability for plants that are built with its technology to be networked together into virtual power plants (VPPs), and are able to be hybridised with batteries or solar to create a more dispatchable, flexible power plant.