C12 Canal Turbine FAQ
1. Please provide a high level description of your technology.
Our canal product is a run-of-river cross-axis hydrokinetic turbine that can produce clean, reliable hydropower without drops or significant engineering. The self-contained units can be installed individually, or along the breadth and length of appropriate sites to increase total power. The non-fouling turbine features a self-clearing rotor and has been designed to be lowered into fast-moving artificial waterways and rest on the bottom – installation within hours, and energy production within minutes. As it does not require any dams or drops, the permitting and engineering burdens are relatively light, making this an attractive and cost-effective distributed renewable energy generation technology.
2. What type of site would be most attractive for a pilot project using your technology?
The most attractive site for a pilot would be in a concrete-lined canal that is easily accessible by road and near a power load (pump, building, etc), with water velocities between 1.5 and 3.0 meters per second. There are thousands of such sites throughout the United States, often found immediately after check structures or in areas with natural topography.
1. What is your nameplate? What is the velocity associated with this nameplate?
The nameplate for our canal turbine is 12 kW, achievable at 3.0 m/s. The turbine’s dimensions are 14’ wide by 5’ tall (6’ including the bottom brace). We are contemplating releasing an international version optimized for smaller canals; nameplate on that should be approximately 5-6 kW depending on final dimensions.
2. What velocity will make the system feasible?
Our flipwing rotor will operate at 1.0 m/s or greater. For economical reasons, however, we prefer canals with velocities between 1.5 and 3.0 meters per second.
3. What is the water depth required for generation? Will the turbine be damaged if not achieved?
The turbines work best when fully submerged (ie – depths of at least 6 feet). As has been demonstrated with the Butte Water District demonstration, the turbine will not be harmed if not fully submerged. Power output, however, will be dramatically reduced.
4. Hydraulic analyses of the impact of a string of turbines in the system?
The products are designed to deploy singly or en masse without affecting overall water delivery. Each turbine installation does result in a small amount of head loss (ie – a few inches of backup). The exact amount depends on the blockage percentage which is driven by canal dimensions as well as water velocity.
5. Generator type and electrical output format
We use a variable speed permanent magnet generator. The turbine produces three-phase wild AC. To connect to the grid, one would rectify power output to DC and then invert it to AC for grid power as appropriate.
6. Interconnection: distribution or transmission system? What about micro-electric grids?
The system can be connected to an electrical grid using inverters that are standard for distributed renewable generation technology, such as those available for solar or wind. Due to the relatively small amounts of power produced, the system is optimized for “behind the meter” connections to the distribution grid. We don’t have any issues with micro-electric grids.
7. How is the turbine installed and anchored?
The turbine is bottom-braced. It simply requires two wire cable anchors, to either a bridge or other feature spanning the waterway, or to the ground on either side of the canal. These are inexpensive features that can be installed in hours.
8. How does the turbine deal with debris?
The turbine is designed to be self-clearing and has never been blocked by debris. The Savonius rotor is both efficient and difficult to foul. The chassis has been designed to maximize swept area and therefore power output while minimizing the amount of brace exposed to the water channel and thus area that can catch debris. Some weeds may catch on the anchor lines and output wires; this can easily be cleared during routine annual maintenance.
9. Operations and maintenance?
The turbine is easily lowered in by a simple boom crane in as little as 90 minutes; it can quickly be removed using the same commonly available equipment. Hydrovolts anticipates annual maintenance to occur during the winter months when the canal has gone dry. This low impact maintenance will be conducted by either the irrigation district or a qualified third party, and has been designed to be straightforward and include items such as cleaning, visual inspection, and bearing lubrication. Otherwise, operational needs are minimal: simply drop the turbine into moving water and watch it generate power.
10. Does your equipment have remote communications available to send alarms if the equipment is not working correctly?
Yes, all products come equipped with standard remote SCADA systems that can communicate distress.
11. What is the anticipated mean time between failures? Is there a typical failure mode that is expected?
We are designing the product for a 20 year lifetime, and anticipate some parts being switched out every few years on a regular basis as part of a preventative maintenance schedule. With the exception of the chassis and the rotor, most parts are off-the-shelf and easily replaceable should a failure occur. The damage to power production wholly depends on which component was to fail.
1. How much does a turbine cost?
We have priced the canal turbines to be competitive with both other renewable and many traditional generation resources. Please contact us directly to learn more.
2. What is the anticipated annual capacity factor? Is this capacity factor based on estimated or measured performance of your system? How do you anticipate generation changing on a seasonal basis?
Generation is entirely dependent upon velocity and water depth. In general, we look for canals that have a minimum depth of 5-6 feet so as to ensure consistent generation. Our capacity factor is 100% – when the canal has water in it, our turbine will produce electricity. Maintenance occurs during the 4 month dry season, leaving an effective capacity factor of 67%.
3. What is the anticipated useful life of these facilities?
We design turbines for a 20 year lifetime.
4. What are the typical fixed annual O&M costs on a $/kW-year basis?
The only fixed maintenance costs are a general inspection cleaning and changing the oil, both of which must occur annually. We anticipate an annual cost of approximately $10/nameplate kW for these two services, including labor.
5. What are the typical variable O&M costs on a $/kW-year basis?
We have modeled variable maintenance costs to be less than $200/kW/year, by looking at the anticipated lifespan of each component and factoring in the cost of both the part and labor for its repair.
6. How do you expect these costs to change over the next 5, 10, 15 years?
Maintenance costs for existing turbines will not change much. However, they should drop for newer generations as information about how parts endure multi-year trials improves.
7. What is the breakdown between development, permitting and construction time?
Hydrovolts needs an 8-12 week lead time to construct a turbine. All artificial waterways (which are Hydrovolts target sites) qualify for a FERC in-conduit exemption, which can take anywhere from 3-12 months. Or, a customer can choose to forego that process entirely and connect to a micro-grid instead. Site preparation and installation can be completed in two days at most.
1. Have you had any consultations with resource management agencies? If so, what environmental issues have they identified with regard to the deployment or operation of your technology?
We have had preliminary conversations with Environmental Resource Agencies in Washington DC, Washington State and California. As canals are artificial waterways and the turbine does not leave a permanent engineering footprint, many environmental concerns are alleviated. As with all engineering projects, the presence of endangered species can throw the project into disarray.
2. Have you had to modify your design or approach in response to agency concerns?
We have never modified our design or approach in response to agency concerns. In fact, our entire business model is predicated on minimizing exposure to environmental and regulatory agencies.
3. Have your performed any environmental testing?
We target artificial waterways so we minimize our exposure to fish and their habitats, so we have not pursued fish testing. However, our turbine is designed so that the dulled-edge blades move at the speed of the water: fish would see a metallic wall and would come to no harm. The turbine does not have any chemical reactions and would not affect water quality.