The 21st Conference of Parties marked an important stage for the global energy agenda. It is popular for the Paris Agreement, which focuses on 1.5̊ C average global warming. According to a report by the Intergovernmental Panel on Climate Change, we will need to achieve carbon neutrality by 2050 to reach that milestone. Cities produce a bulk of the global gross domestic product (GDP) and host more than 50% of the global population. By 2050, estimates show that this percentage will have risen to almost two thirds. Simply put, cities hold the key to the goals we are trying achieve within the next three decades. District energy is an ideal way of not only providing energy to cities, but also mitigating climate change. Alternatives continue to present competition, so potential users are sometimes confused. In the next part of this article, we highlight the benefits of district energy compared to traditional solutions.
Benefits of District Energy are Irresistible
The initial concept of district heating and cooling systems is to use local resources to minimize carbon dioxide emissions and primary energy demand. For district heating, this idea of how does district energy work is presented below.
Fig 1: District Heating Concept
This basis gives the district energy systems superiority over other alternatives in several ways.
A district energy system operates in a simple way, as long as its installation and tuning is correct. It works automatically, providing cooling or heating at the preset temperature. This system provides the required comfort on a 24/7 basis. The desired comfort in different rooms, shops or offices can be adjusted individually since the system responds swiftly to any demands. Users do not have to worry about incessant noise and vibrations related to conventional solutions.
Simple Equipment and Minimal Maintenance Requirements
Individual buildings relying on district heating and cooling systems do not require own chillers and heat pumps or boilers.
Fig 2: Inside a District Cooling PlantThis translates into substantially lower upfront costs and maintenance/operating costs.
District heating idea can be traced back to adoption of surplus heat from industrial processes, cogeneration and so forth. This heat would otherwise have gone to waste. There is probably no better way of minimizing or avoiding application of fossil fuels. Furthermore, the system can rely on a wide range of local resources including sewage sludge, wood waste and municipal waste. The fact that district energy consumes very little primary energy and emits less carbon dioxide has a significant impact on agenda of a sustainable environment.
Reliable and Highly Efficient
District heating and cooling systems are highly efficient, and are renowned for reliability, backed by a wide range of fuels supporting the production facilities. Coal fired power plants used for utility electricity have efficiency of between 35 and 45%. A district energy system with a combined heat and power (CHP) setting can achieve as much as 80% efficiency.
Role Played by Traditional Heating and Cooling Systems
The level of thermal loads and customer density sometimes favors the installation of conventional hot water systems and space heating/cooling systems for individual buildings. That is why these solutions are still relevant despite the growing popularity of advanced district heating and cooling systems. Even when such factors suggest that district heating and cooling systems would be more suitable, some cities still opt to cling to conventional technologies. The fact that DE systems are capital intensive does not augur well with some real estate developers who want extremely quick return on investment. Most of these developers prefer return on investment of not more than two years. If you do not have cooling or heating data, it becomes difficult to appreciate any cost benefits of district energy. Some building operates are unable to correctly compare the values for district energy and conventional solutions. A true cost comparison goes beyond cost of production vs. energy cost. Other considerations include cooling tower, make-up water, operations, life cycle costs, utility costs and pumps. Prevailing energy policies may also favor established technologies. Take for instance Scandinavian countries that have strong policies that support district cooling systems as compared to the United States where the policies is not as robust. The good news is that support for district energy is growing in different cities.
It is undeniable; there are many benefits of district energy. This technology has demonstrated superiority to traditional solutions in many ways. If population density and thermal load conditions allow, increased resiliency, better energy savings, improved money savings and minimized GHG emissions are strong enough reasons for cities or campuses to make the switch to advanced district heating and cooling systems. Contact us to learn more about our district energy solutions, including district cooling, district heating and thermal energy storage.