Ashden Winners

Dulas / Employee-owned renewable energy business

Area of work:

Play Video

Dulas, based in mid-Wales, is an employee-owned business.

Now nearly 30 years old, it has built up a wealth of practical experience in all aspects of local renewable energy. Its work in the UK includes micro-hydro (design and installation); wood-fired heating (design, installation and management); wind (monitoring, environmental impact assessment and installation of small systems); and solar energy (installation and provision of wholesale supplies to other installers).

By 2008, about 7 MW of small-scale hydro installed...

...and over 0.5 MWp of solar PV installed.

Saving about 4,500 tonnes/year of CO2.

"We like to be able to tell visitors that we’re not using coal or oil, especially as our work is all about trees."

Ranger at Forestry Commission visitor centre


Volunteers founded the Centre for Alternative Technology (CAT) in Machynlleth, Wales in response to the oil shocks of the 1970s. Their focus was on both living as a sustainable community, and acting as a practical demonstration of sustainable technologies, open to the public.

In 1982, six engineers from CAT set up the renewable energy company Dulas. Their aim was to provide professional renewable energy services on a commercial basis, but operating with a strong community ethos. The mission of the company is to improve lives through renewable energy and sustainable technology, and it retains close ties with CAT.

Dulas’ low-energy headquarters in Machynlleth has a solar roof on its bicycle shed.

The organisation

Dulas is owned by its employees, who elect the board of five directors on an annual basis. It has no external investors and is financed largely through sales. In 2007 its turnover was £7.8 million.

In 2010 Dulas had 80 employees at its headquarters in Machynlleth, making it one of the largest employers in the area. The headquarters occupies two modern energy efficient buildings, which have achieved BREEAM excellent rating. A Scottish office in Stirling was also opened in late 2010.

The company provides technical services in hydro, solar, biomass and wind energy, and also provides planning advice, feasibility studies, project management, environmental impact assessments and consultancy.

The technologies


Dulas is one of the few companies in the UK that is able to specify, build and operate small run-of- river hydro schemes, and works throughout the UK. A typical scheme uses a screened intake, from which water is captured and fed down a penstock to the turbine, which drives a generator to feed electricity into the national grid. Various types of turbine are used (from 10 kW to several megawatts), according to the volume of water and the height from which it is falling. Dulas also refurbishes existing hydro schemes, including some that are over 100 years old.

The weir at the water intake for a small hydro turbine.


Dulas carries out its own solar PV installations, but also sells modules through its wholesale channel to its UK-wide network of installers. A typical system uses an inverter to connect the PV modules to the building’s electricity supply; electricity generated is used within the building, and any surplus is exported to the national grid. Customers include housing associations, schools, community groups and industrial clients.

In addition to its work in the UK, Dulas also has a significant global business in solar PV. Products include solar-powered water pumps,

lanterns and DVD players, but the most significant is the vaccine refrigerator. Dulas currently has about 75% of the world market in vaccine refrigerators, with the main customers being the World Health Organisation and UNICEF.

Solar PV arrays installed by Dulas at Dyfi Eco Park.


Dulas carries out feasibility studies and resource assessments for biomass, and also installs boilers burning wood chips, wood pellets or logs. Some boilers supply single buildings with heating and hot water, others supply district heating schemes in which a number of buildings are supplied from a single boiler using an underground ‘heat main’.

All biomass operations are within Wales, so that Dulas can ensure that a reliable supply of good quality fuel will be available for the customer. It works to help local wood-fuel suppliers build up their businesses.


The company carries out site assessments and installations for small turbines. It also works on large-scale wind power projects, providing services such as site identification, feasibility studies, environmental impact assessments, wind monitoring, wind resource assessment and planning.

Solar PV arrays installed by Dulas at Dyfi Eco Park.

How is payment made?

Payment for products and services is usually in stages, after specification, installation and commissioning are complete.

Dulas has also created some alternative models for funding renewable energy installations.

One is Dulas Hydro Generation, which takes private investment and uses it to fund the capital expenditure for hydro schemes, including new build and refurbishment.

Another model is the Renewable Energy Investment Club (REIC) which aims to promote community-owned renewable energy installations by enabling a developer to issue shares to local investors. The club has delivered one successful project, owned by Bro Dyfi Community Renewables.

Dulas also works with the Energy Services Company (ESCO) payment model, and operates four ESCOs linked to biomass boilers that it has installed. In each case the customer pays for the heat delivered, while Dulas manages the fuel supply and operation, and organises a local supervisor for day-to-day management.

Cath Peasley, with examples of the Dulas solar powered vaccination fridges.

How is technology installed and maintained?

Dulas provides detailed training to all of its installers to ensure they are competent to carry out work on its behalf. The company is certified to ISO:9001 for quality control.


By 2008, Dulas has installed about 7 MW of small-scale hydro in the UK; over 0.5 MWp of solar PV (with considerably more sales to its installer network); 14 biomass projects with a total capacity of 1.3 MW; and seven small wind systems with a total capacity of 20 kW. In addition, consent achieved for 235 MW of wind capacity in the UK, and over 2 MWp of PV vaccine refrigeration systems had been sold internationally.

Environmental benefits

The renewable energy installations undertaken by Dulas generate approximately 10GWh/year of electricity and 2 GWh/year of heat. The associated carbon saving is around 4,500 tonnes/year CO2.

Volunteers founded the Centre for Alternative Technology (CAT) in Machynlleth, Wales.

Other benefits

In line with its mission ‘to improve lives through renewable energy and sustainable technology’ Dulas has always worked with schools and community projects, providing educational support as well as technical services.

Dulas offers six-month trainee positions to new graduates, enabling them to get crucial work experience in renewable energy. Many of these trainees continue to work for Dulas after their training is completed.

Internationally, the PV vaccine refrigerators especially are vital to improving the health of communities who have no access to grid electricity.

Potential for growth and replication

Dulas is an employee-owned business, and has opted for organic, planned growth rather than rapid, step-change expansion. A key strength of the company is that it does not rely on a single technology for market growth. Expansion has been rapid during the past few years, and all the divisions within Dulas are growing.

Read More / Related posts

This site uses cookies to provide you with the best user experience. By using the Ashden website, you accept our use of cookies.

Stay up to date

Be the first to know about our latest projects and news