Scotland has been successfully using run-of-river hydropower for over a hundred years. Its mountainous terrain and high average rainfall that feeds the lochs and rivers provide numerous opportunities to produce renewable low carbon electricity, particularly in rural areas across the country.

Scottish company Green Highland Renewables (GHR) has specialised in the development of small scale hydro schemes since its formation in 2007 when two Perthshire landowners, Alastair Riddell and Iain Wotherspoon, realised the extent of hydro resources.

In 2008, Scottish and Southern Energy (SSE) Venture Capital took a third share in the company, as it considered GHR offered a complementary service to its own hydro portfolio, operating at a development scale not offered by SSE. In 2011 SSE’s holding was transferred to Scottish Equity Partners LLP’s (SEP) Environmental Energy Fund LP, of which SSE are 50% shareholders. In 2012 SEP and Scottish Enterprise invested significant funds worth £3.3M into GHR. This will allow the company to develop its growing pipeline of hydro-generating sites, as well as to provide a wider consultancy, project management and operation and maintenance to clients.

Ian Cartwright, Managing Director of GHR, said: "We are delighted to have closed this substantial investment round. Hydroelectric site development is a complex process, from prospecting to commissioning. It is therefore important that the company has access to substantial development capital to enable us to take advantage of the growing number of opportunities. This injection of capital means, in addition to servicing demand from our existing clients, we can actively seek out new clients requiring help with site development. We are actively looking for more schemes that we can develop with landowners. These schemes, once completed, can provide landowners with long term relatively risk free income."

The investment was accompanied by restructuring of the board of directors, with Paul Capell appointed as the new Chairman. His 30 years of experience across the renewable energy and water sectors, combined with Cartwright’s skills and experience of renewable energy delivery in Scotland, are driving forward an ambitious business plan to develop, construct and operate hydro schemes across Scotland.

GHR has worked on a wide range of run-of-river schemes throughout every phase of the development process from initial concept through to consent, construction and operation as well as providing remedial works and scheme optimisation. It has been involved in the development of over 20 private hydro schemes and has developed 18 schemes as part of a lease or partnership arrangement. The projects have ranged in size from 100kW-2MW. A further portfolio of schemes is also currently being developed in partnership with Forestry Commission Scotland.

National Forest Estate
In October 2009, the Forestry Commission Scotland (FCS) split the national forest estate into three separate regions (or lots) with the intention of appointing commercial partners to help it investigate and deliver run-of-river hydropower projects. The scheme is part of an overall Scottish Government drive to generate clean and renewable energy and reduce the effects of climate change.

GHR was appointed in August 2010 to progress Lot 3 which covers the north and west of Scotland and the company has been working with the commission over the past 18 months to explore the sites. Two sites have now been submitted for planning approval, both near Loch Garry, and a further three are expected to be submitted in the first quarter of 2013. Further investigative work is being carried out on a number of other sites that will progress throughout 2013.

Kevin Peace, Forestry Commission Scotland’s District Manager in Lochaber said: "Scotland’s national forest estate is making its contribution to the production of clean and renewable energy by working with Green Highland in the development of a number of small scale hydro projects. Developing renewables on the national forest estate is always to be carried out in a manner that is sensitive to the environment, and through the planning process is subjected to thorough scrutiny. Communities and neighbouring landowners will continue to be consulted as part of the planning process and constituted community groups are eligible for generous community benefit payments and have the option to invest in the schemes."

Case study: Roroyere hydro scheme
Roroyere hydro scheme is another small scale project GHR has been working on. Located on the Allt Gleann Da-Eig, a tributary of the River Lyon, it is one of seven hydro schemes developed as part of the Glen Lyon Partnership (4MW) which was formed between landowners in the glen. Its purpose was to aid co-operation in the development of available hydro potential. Large grid connection costs will also be shared between the seven projects to ensure that the whole project is financially viable.

Glen Lyon has numerous environmental designations such as National Scenic Area, Sites of Special Scientific Interest and Special Areas of Conservation. This is due to the number of significant receptors in the area including Atlantic salmon, otters and freshwater pearl mussels. All sensitivities were thoroughly analysed and incorporated into the design in order to safeguard the environment.

The scheme generates approx 2500MWh of energy per annum, enough to supply approximately 500 average sized households. The power which is generated is sold to the grid and the project is one of the first hydro projects in the UK to benefit from the Feed in Tariff scheme (FiTs) which provides renewable generators with a guaranteed energy price.
Roroyere is a typical run-of-river project. The main scheme components are:

• Weir structure – A screened intake across the river using a Coanda washover screen, designed to abstract water at 630l/sec.
• Penstock – Buried pressurised pipeline (700mm PE pipe) that takes the water from the intake to the powerhouse.
• Powerhouse – buried design containing a 800kW Pelton turbine and generator and control system.
• Outfall – discharge point back into the associated watercourse.

The Roroyere scheme was constructed using a multi-contract approach, with separate contracts awarded for the civil design, project management, civil engineering and mechanical and electrical plant and installation.

Construction started on 19 July 2010 and the completion certificate was issued to the civil engineering contractor in April 2011. Despite the fact that a significant amount of work took place over the winter of 2010/2011 when the weather was extremely challenging, the majority of civil works was still completed in this timescale. There was a significant delay on the turbine delivery date which consequently delayed testing the pipeline penstock. The original date for the turbine delivery was early April 2011 but was delivered three months later. Furthermore there were a number of issues relating to the pipeline testing which delayed commissioning further. The turbine was exporting to the grid with all restrictions lifted by the end of November 2011.

The scheme came in on budget and represents good value for money for a hydro scheme of this size and location. GHR also said that its procurement and project management approach has gained from the experience of developing the Rororyere scheme. Procedures for selection and scheduling of the mechanical and electrical equipment have been developed to reduce the risk of delays occurring in any other scheme.

With the 2011/12 winter being wetter than average, power generation figures for the Roroyere scheme from November 2011 were significantly higher than expected. Conversely the 2012 spring was drier than average and therefore generation figures were marginally less than expected for the first three months in 2012.

For more information please contact Anna Douglas