Tom Clegg is the Head of Hydropower at Fichtner Consulting Engineering in the UK. With the current pumped storage landscape, he believes it is a very exciting time to be a hydropower engineer

Fichtner. Glyn+Rhonwy+QUARRY

Fichtner is currently engaged in several pumped storage schemes in the UK, including the Glyn Rhonwy pumped storage project in North Wales

Fichtner is an engineering consultancy working across all generation technologies and power infrastructure. Headquartered in Stuttgart it celebrated its centenary year in 2022. Globally we have almost 1800 colleagues with a presence in over 60 countries.

My role is Head of Hydropower in the UK and Irish markets. I am responsible for managing our hydropower activities within the territory, leading business development and coordinating with the centre of expertise in Stuttgart. This includes managing projects within the territory and acting as a technical specialist in my area of expertise.

Fichtner is currently engaged in several pumped storage schemes in the UK. This includes the Glyn Rhonwy pumped storage project located in North Wales. The scheme is interesting in that it will utilise two disused slate quarries to form upper and lower reservoirs with a total generating capacity of 100MW. Aside from this project in the tender design stage, we are working on a number of projects in the earlier stages of development.

Internationally Fichtner is supporting the Estonian Paldiski project. This is particularly interesting as it utilises what the developer Energiasalv Pakri OÜ terms the “Zero Terrain” concept. In this concept, no mountains are required, and the lower reservoir is located in caverns beneath the ground. The upper reservoir is the Baltic Sea on this occasion with a gross head of over 500m and a generating capacity of 500MW. We are currently supporting our client with FEED engineering and preparation of tender documentation for the construction contract. Another significant project is the Kokhoav Hayarden Pumped Storage Project located in Israel. Fichtner, as the owner’s engineer, is supporting our client Star Hydro with design review and construction supervision. The 340MW scheme is currently in the construction phase.

Pump IT tool

To assist our clients interested in identifying and evaluating potential new sites for pumped storage we developed the Pump-IT tool in 2010. The model has been further developed since and covers the topography of the investigated area, its land use, infrastructure, geology and other characteristics. Algorithms estimate geometrical properties of schemes, the distance to the grid, etc. The method enables an automated screening of large areas, to identify and rank pumped storage projects. An overview of the method is provided below.

Methodology

Geographic Information Systems (GIS) are designed to manage and analyse geographically referenced data and are a common tool in a number of fields of civil engineering, such as in infrastructure planning and hydrology. The parameters which give merit or disadvantage to a project site are fed into a GIS-model and analysed in order to extract the most suitable areas for developing pumped storage schemes.

The identification of potential projects and the estimate of the capacities are accomplished in a top-down process in the following steps, as identified in Figure 1. The developed method allows screening large areas throughout their extents and selection of the most attractive projects.

GIS-Based Screening

The GIS-model is based on a number of sources of geo-information, such as topography and protected areas and is equipped with different algorithms and filters. The algorithms were developed to remove no-go areas or unfavourable cells from the model as well as to identify suitable areas with favourable properties.

GIS-Based Ranking

A variety of criteria is associated with every identified project. The ranking of the projects is based on the criteria that can be selected and weighted in accordance with the client’s needs. As a result, the top-ranked projects are listed in Class C-Projects.

Cross-Check

The resulting Class C-Projects are subsequently checked based on satellite imagery and available maps. In the course of the cross-check, some projects are sorted out that do not qualify due to one or more of the following reasons:

  • Existing settlements,
  • unfavourable dam site geometry
  • other no-go area; or
  • Already pumped storage plant constructed at the site.

The remaining projects are pairs of upper and lower reservoirs named Class B-Projects.

Confirmation of Parameters

The parameters as calculated in the GIS are now confirmed by an engineer. The confirmed Class A-Projects are displayed in a data sheet. The next step would then be to perform a site visit and conduct a pre-feasibility study.

We then compare the results of the study to the existing pumped storage plants in in the screened area. Typically, it has identified the vast majority of existing pumped storage plants.

UK pumped hydro opportunity

Pumped storage has a very special opportunity in the UK at the moment. Huge capacities of wind and solar generation are currently being deployed into the national grid in our efforts to transition to a net zero economy. The industry recognises that a bulk energy storage technology is necessary to offset these intermittent generation sources and allow their dispatch when required by consumers. Pumped storage is extremely well positioned to fulfil this requirement with its maturity, long asset lifespan and ability to store at a GWh scale and dispatch that power on demand at scale.

The UK government is considering this area for support and has released several calls for evidence on long-duration storage in recent years. The industry is engaged with this consultation process, and we hope to receive further positive feedback from the government in the near future to support newly built pumped storage in the UK.

Considering the current position in the UK, this is a very exciting time to be a hydropower engineer. We have three new build projects with planning consent and many more projects being brought forward by developers for consenting. We have a rich heritage of schemes developed by the North of Scotland Hydro-Electric Board and the Central Electricity Generating Board, while pumped storage schemes such as Dinorwig and Cruachan remain integral to the stability of our national grid.

I hope we will have the opportunity, as the current generation of hydropower engineers, to witness a new generation of pumped storage hydropower schemes in the UK.

This article first appeared in International Water Power magazine.