Hydro Feasibility Studies, Hydro Pre-Feasibility Studies & Hydro Consultants
A hydro feasibility study is an important piece of work which forms the foundation of the future project. It is vital at this early stage that the data used is as accurate as possible and that the work is done by a company that designs and builds hydropower systems; otherwise they will not have the specialist knowledge and experience required. All of our feasibility-stage work benefits from over ten years of experience of designing and building hydropower systems, and we have conducted feasibility studies on more than 300 sites throughout the UK!
Renewables First provides a range of hydro feasibility services and hydro consultancy services including site surveys, pre-feasibility studies and full feasibility studies. We work closely with the client to understand their needs and expectations and get the scope of the study correctly defined at the beginning. We think of the feasibility as the start of a long relationship which will hopefully result a working hydropower system, so it is worth the effort to start off on the right foot. Click on the links below to jump to the relevant section:
- Full Hydro Feasibility Study
- Hydro Pre-Feasibility Study (including hydro site survey)
- Hydro Consultancy
 |
 |
 |
Full Hydro Feasibility Studies
The aim of a full hydro feasibility study is understand the site, accurately work out how much head is available and what the flow characteristics are, and then specify the optimum hydro system. Then the system performance can be modelled, the annual income calculated and project costs estimated. Final everything is summarised in a report with conclusions and recommendations made. The main sections in our standard full hydro feasibility are outlined below:
Hydro site survey
Hydropower systems have to be ‘bespoke designed’ to fit into a site, rather than onto a site as is the case with wind turbines, so the site survey is particularly important. A key element of the hydro site survey is to get a good understanding of the layout of the weir(s), channels, sluices and surrounding buildings so that some initial options for locating the hydro system can be discussed with the client. We take accurate measurements across the site so we can work out the gross heads (differences in water levels) between all key points. The on-site and nearby electrical distribution infrastructure is also checked and any details available recorded, along with checks on site access for construction and delivery vehicles.
Hydro flow modelling
Accurate flow estimates are vital because they form the basis of the performance and income predictions for the hydro system and are a key element when specifying the most appropriate hydro turbine. We use LowFlows II hydrological catchment modelling software, and whenever possible use the software to calculate accurate correction factors which can be applied to the nearest EA / SEPA gauging station data so that the estimated site flow data is based on real flow data. The results are presented as a site Flow Duration Curve and a summary table. This flow data can then be used during all of the subsequent discussions with the environmental regulator.
Hydro head analysis
This is based on the gross head measurements taken during the site survey, then we take into account head losses in channels and pipework to produce an estimated net head (i.e. head after head losses are taken into account) which is then used in the hydro system performance modelling. Our in-house modelling software also takes into account changes in the head across the site as the flow rate changes and upstream water levels rise and downstream levels back-up.
Hydro system sizing
This is where experience really starts to count. It is important that both the best type of hydro turbine is specified for the combination of head and flow at the site and also that it’s maximum flow rate and flow operating range are selected to maximise energy generation, and therefore income. There are some additional factors that we also consider, including the availability of the specified turbine and standard runner diameters, physical site constraints that may restrict the maximum flow rate plus we also consider fiscal constraints such as Feed-in Tariff banding. There is an optimum sizing solution for all hydro projects and it is important that is correct from the start.
Hydro hardware selection / specification
Renewables First works with all of the leading hydro turbine (including Archimedean Screw) manufacturers, but is not tied to any particular technology or manufacturer. This means that we can provide truly impartial advice and you can be assured that we will specify the most appropriate hydro turbine for your site. We will only specify good quality tried & tested hardware from reputable manufacturers.
We have experience of turbines from all of the leading suppliers and have a detailed reference database to draw 
upon, including designs from previous projects. We can also base the hardware costs on real quotes from previous projects or can quickly get updated prices from the manufacturers to ensure the hardware cost estimate is as accurate as possible.
Once the hydro turbine has been specified we can then specify the most appropriate drive system (belt, gearbox or directly-coupled) and the generator and control system.
Review existing infrastructure
This is a review of what is already at the site and how this can used with the proposed hydro system. For example using existing bypass sluices to lower water levels at the hydro intake screen for maintenance, or using an existing building to accommodate the hydro turbine.
Hydro system layout
Based on the work so far we will sketch the system layout onto a suitable map (normally a google earth image), approximately to scale. This includes the intake screens, intake channels and / or penstock pipework, the turbine house and any discharge channels or pipework. This gives the client a good idea of the physical scale of the proposed hydro system so that if any fundamental changes are required they can be discussed before the more expensive design stages begin.
Hydro performance modelling / energy production estimate
Renewables First has developed its own complex modelling software for hydro system performance estimates. The flow and head duration data for the site is the foundation, and then the selected hardware is added to this to build a complete mathematical model of the proposed hydro system. The modelling not only takes into account changes in head across the system due to upstream and downstream water level changes, but also calculates the head losses in all components in-between depending on the flow rate. Added to this the efficiency of the turbine, drive system and generator are calculated independently depending on the load. The end result is a performance prediction that is remarkably close to real-world operating experience.
Grid connection appraisal
Depending on the size of the system we either complete this work in-house or use a specialist grid connection consultancy to assess the local grid strength and recommend the most cost effective way of connecting the system to grid. Where possible (and if desired) we would aim to grid-connect through the site’s existing distribution board so that the site owner would get first use of the electricity generated (which is the most cost-effective option).
Environmental & planning consents
We check the site for any ecological and landscape designations that could affect the consent applications, along with a check of the environmental regulators plans for the watercourse. Then based on our nationally recognised expertise on hydropower licensing we will outline what EA or SEPA consents are likely to be required, plus any Local Authority planning consents.
Hydro budget cost estimate
Again this is a key part of the feasibility study which benefits greatly from years of experience of actually designing and building hydropower systems. We use data from real previous projects and standard construction industry pricing guides to make realistic estimates of hardware and civil engineering costs, along with estimates of the consenting and design fees required for the next project stages.
Financial analysis
This takes the energy production estimate and marries this with the most appropriate Feed-in Tariff and export rate, plus includes any financial benefit from offsetting grid-imported electricity to produce realistic income estimate. Next we take the budget cost estimate and estimate when those costs would be incurred and build a project cashflow model. Built into the model we include operating and maintenance costs so that realistic bottom-line financial results can be calculated.
The results are presented as a cashflow chart over first 25 years of the project, which clearly shows the initial outlays and then the income repaying those outlays once the system is operating. This clearly shows the payback period, then separately we calculate the Internal Rate of Return (IRR) and Net Present Value (NPV).
Next we carry out a sensitivity analysis to show how the operating income could vary between dryer and wetter than average years, and also show how the income varies seasonally. Although we can’t predict the future, this shows the how income could vary depending on the weather.
Recommendation and next steps to progress the project
We provide an overall recommendation on whether the project should proceed and highlight any potential issues. We also provide a map of the project stages to completion along with a timeline.
Hydro full feasibility study price
The price varies depending on the expected maximum power output of the finished system:
- Less than 100 kW £3,100
- 100 - 250 kW £3,600
- 250 - 500 kW £4,700
All prices plus travel costs and VAT.
| |
|
|
Hydro Pre-Feasibility Study / Hydro Site Survey
Our hydro pre-feasibility studies aim to quickly establish if a site has the potential to be developed as a hydropower site. The report is desk-based and uses on-line resources and specialist software, plus input from the client. The scope is necessarily brief in line with the cost, but includes the following:
- Initial head estimate
- Initial mean (average) flow estimate
- Initial check of site sensitivities that may affect licensing and consenting
- Site review to determine the most appropriate system location
- Initial turbine sizing
- Power output and energy production estimate
- Income estimate
- Budget cost estimate
- Conclusion and recommendation on whether to proceed to the full feasibility stage
All of the above is summarised in a concise report. The price is £620 + vat.
In addition, we can also carry out the site survey as if we were completing the full feasibility study. This gives the opportunity to have a good look at the site, measure the head precisely and discuss all of the options with the client. The more detailed data collected during the site visit can then be fed into the pre-feasibilitystudy to produce a more accurate result. If the project then proceeds to the full feasibility stage the cost of the site survey would be offset against the final bill.
The cost of the site survey is £620 + travel costs + vat.
Hydro Consultancy
Some projects don’t fall neatly into our standard full hydro feasibility study and hydro pre-feasibility study packages so a bespoke service is required. This is particularly the case for upgrades to existing hydro sites or integrating hydro systems into existing water infrastructure, such as process water outfalls or water treatment works. Also tidal hydro sites where impounded tidal water would be released through a low-head hydro turbine.
We’ve come across most applications for hydropower, so can draw on our previous experience and deep knowledge of the technology to find a solution.
We can also provide site-finding services, from finding the actual sites, identifying site owners and arranging all of the legal paperwork that needs to be in place before the site can be developed.
