Task 24
Task 24
SHC Task 24

Active Solar Procurement


Solar hot water systems in the Apeldoorn, the NetherlandsEnergy utilities in a number of countries are taking advantage of solar water heating for their businesses. Currently 1.3 million European households use solar water heaters, replacing 215*106 m³/year of Natural Gas or 2300 GWh/year. Many of these installations have been completed by energy utilities (see ref 1) . Solar water heaters, typically installed on building roof-tops, produce around 50% of the hot water load through solar energy, with the balance being made up by electricity, natural gas or oil. While the current emphasis is on water heating, there is also potential for growth in solar home space-heating.

Expansion of Market Share for Gas Utilities

Danish gas utilities have successfully employed the positive aspects of solar water heaters in their marketing strategies, to increase market share of natural gas. One Danish utility, Naturgas Midt-Nord, has attributed a 60% increase in gas sales (878,000 m³) (see ref 2) to their marketing campaign, which combines solar water heating and natural gas. The competitive positioning is that the solar-gas combination is a more environmentally friendly package compared to oil or electricity.

Achieving CO2 Reduction Targets and Creating Corporate Goodwill

The Dutch utility, Nuon, has already facilitated the installation of approximately 7,500 solar water heaters through a well-developed project approach. This on-going venture provides utility customers with reliable, cost-effective water heating by combining solar energy with the base fuel. Each installation contributes around 300 kg in annual CO2 reductions.

Nuon has also benefited by taking a leadership position with respect to emission reduction targets, and has succeeded in turning this issue into a winning business strategy, promoting public goodwill for the utility. As a direct result of this programme, the utility has received extensive positive publicity both locally and internationally.

New Customer Choices

Many utilities are finding that their customers are asking for new product and service choices. These customers are motivated by the increased expectations that accompany deregulation and competition, as well as by an increased understanding of environmental issues. There are many markets where customers have expressed a strong desire for "green" energy products. Some customers demonstrate a willingness to pay more for "green" energy (21%, MORI opinion poll (see ref 3), UK; 11%, Ontario Hydro, Canada (see ref 4)). However, significantly more customers express a desire for "green" energy if the price is not higher (65%, MORI opinion poll, UK; 30%, Ontario Hydro, Canada).

Retailing Opportunities

In the UK, some of the recently deregulated energy companies have added solar water heaters to their retail product mix. These utilities use their billing service to offer customers energy-related products such as solar water heaters. Some utilities also offer financing packages to assist sales growth.


Several solar water heating projects have been conducted by Utilities and are summarized in the following case studies:
Natural Gas Utilities
Case 1 Natural gas in combination with solar heating systems
Case 8 Swimming pools/Rupchen
Case 9 "Zonnelease"
Electric Utilities
Project 1 Sunshine over Thy and Mors
Case 4 Electricity utilities
Energy Supply Company's
Project 4 Essent New Housing Project
Project 7 Zug
Project 8 Lucerne
Case 3 Sun and/or biomass in sparsely populated areas
Case 5 Large scale sales to private individuals/Leiden
Case 6 Large scale sales to private individuals/Utrecht
Case 7 Apeldoorn solar project


Utility Access

General Advantages
  • Sell more gas
  • Use contact to customers
  • Strong local participants
  • Inexpensive homogenous plants
  • Marketing
  • Good neighbor impact
  • Utilities show the way (save/improve their reputation)
  • Advice & inspection included

Projects with Solar water heating/biomass plant.

Two cases include the combination of solar water heating and a biomass plant.

Solar water heating in combination with biomass plant.

General Advantages Lessons Learned
  • Complete heating plant
  • Spare work with biofuels in summer
  • Inexpensive plants
  • Positive neighbourhood impact
  • Development of technical solutions
  • Expensive
  • Lack of technical experience
  • Not so much marketing









  1. P.G. Out, C.J. van der Leun, Ecofys Research and Consultancy, "Realizing 10,000 Solar Water Heaters by the "Project Approach": lower cost, higher quality", Solar Energy & Utilities Conference, Vejle, Denmark, 1997.
  2. Klaus Ellehauge, Solar Energy Laboratory, Danish Technological Institute, personal communication, 1997.
  3. Madeline Wood, ETSU, United Kingdom, personal communication, 1997.
  4. Ontario Hydro, Canada, market research survey results.