HOT|COOL NO. 1/2017 - "System Integration"


By Anders Dyrelund, Senior Market Manager, Ramboll

Wind energy is becoming a dominating renewable energy source in Northern Europe. Fluctuating wind and solar energy (PV) calls for energy storage. Electric batteries are extremely expensive, but we have smarter solutions. District heating and cooling systems, DH&C, which can use electricity based on wind anyway, can transfer the electricity to thermal energy and store it for later use much more cost effectively than batteries. Besides, CHP plants can generate electricity when the wind is not blowing. Seen from the electricity system, the DH&C system acts as a battery. In typical new urban developments, the smart energy system with virtual battery is cheaper than individual less smart heat pump solutions. In existing DH systems, large-scale solar heating can be a driver for large seasonal storage facilities, which have free storage capacity for the integration of fluctuating electric energy.

The smart energy system Ramboll has for The Danish Energy Agency analysed the benefits of a smart energy system integrating renewable energy and found that DH&C with its large thermal storage is vital for this integration. Denmark is in a fortunate situation as the cities have already developed city-wide district heating systems to use surplus heat from waste, large-scale solar collectors, biomass and CHP. Cities for which energy planning is new may find it difficult. However, as cities grow, there is an opportunity to plan for smarter solutions, benefitting from the economies of scale factors in the cities.

Figure 1 illustrates the smart energy infrastructure as it could be in a typical Northern European city.

Figure 1 illustrates the smart energy infrastructure as it could be in a typical Northern European city.

Planning smart energy EU has discovered the benefits of smart energy systems in a package of directives. The Building Directive states that buildings shall be low-carbon buildings taking into account that renewable energy and CHP can be transferred to the buildings via DH&C. The Renewable Energy Directive and The Energy Efficiency Directive state that local authorities shall plan for DH&C to integrate and use renewable energy and CHP. Implementing a smart energy system Consumer empowerment and public control of the natural monopoly grids have inDenmark been adriver for implementing the smart energy system. Consultants, suppliers, contractors and banks compete in a transparent market to the benefit of the society and the consumers. In some countries, consumers and local authorities have difficulties in finding their roles. Large areas or districts with the same owner, like for instance campuses have, however, no problem in implementing the smart energy system as the owner has the same interest as the consumers.

• The green electricity grid transfers wind energy to buildings, avoiding suboptimal production at building level.

• The yellow gas grid supplies industries and CHP and distributes biogas.

• The red district heating distributes low temperature heat to all buildings.

• The blue district cooling is the new infrastructure in city centres.

• The smart buildings have integrated low temperature heating and high temperature cooling.

In the liveable city, energy and environment facilities are located in the “smart backyard” of the city benefitting from industrial symbiosis. Standing on the roof-tops, one cannot hear, see or smell any sign of energy activity.


Made with FlippingBook Ebook Creator