The IS 666 of 2006 approves District or Block heating or cooling (if available) for the purpose of inclusion as Alternative Energy Systems for use in large buildings seeking compliance and BER . A large building is defined as a one where the usable floor area is 1000m2 and over for the purpose of granting BER.
Have you ever wondered what a District Heating or Cooling system is?
To put it simply it refers to a system where a heated medium (or a cooled medium as the case may be) is distributed from a centralized location of generation.
The system would incorporate (considering a heating system and water as the medium for convenience of illustration);
- The Heat Energy generation equipment
- A distribution net work of insulated pipes
- Circulating equipment and power supply
- Hot water buffer storages
- Valves, gauges and Controls
- The heat exchangers interfacing with the end users own hot water circulation system
The Hot water or steam circulating net work of insulated pipe is generally run underground which method offer improved insulation and mechanical protection.
The inherent disadvantage is being out of sight maintenance is a bit cumbersome.
The Purpose of a District Heating System (DHS) is to provide heating for;
- Space Heating
- And Hot water
This may be for either domestic or industrial purposes. In practice a loss of approximately10% of the total heat being circulated has been observed in DHS in colder climates.
The all important heart of the system, the Thermal Energy generation equipment is located remotely and generally takes the form of a CHP also called a Cogeneration plant, which is an SI 666 approved heating system. The Thermal Energy generating equipment can also be a “Heating only” boiler. The medium of heat transfer in this case could be Steam instead of water (most cases). Presently however geothermal energy, Central Solar Heating, Nuclear Power Plants etc. too are incorporated in District Heating Systems.
The thing to take into account in a CHP is you would get Heat and Electricity while in the “Heating only” boiler it is just that only!
(Of course Nuclear Power Plants are out of contention as far as the capacity and the scope of SI 666 is concerned).
The facts in favor of CHP for your district heat application are;
- A CHP can be operated on a number of fuels. eg. Diesel, Gasoline, Natural Gas and biomass etc.
- The CHP operated District heating systems are more energy efficient and have better pollution control than localized boilers.
- The CHP sizes start from 20 kw (electrical) upwards
- Being up to about 85% efficient overall, for a community of reasonable population it is an ideal self sufficient energy system.
- It is a recommended type of system for the large buildings in the context of renewable energy applications.
The BER as an index of over all energy efficiency and sustainability of a large building (or a community of large buildings) is likely to take in to account a District Heating System in a much favorable light for a higher rating. However it is imperative to study the intricacies in detail from the initial design stage to obtain the best benefits for the occupants as well as the developers.
Building Energy Rating (BER) assessors registered by Sustainable Energy Ireland (SEI), who carry out
BER assessments on existing and new houses, single or in developments.
An assessor will assess the dimensions, fabric, ventilation, water heating and lighting systems in your building.
This will then be used to calculate an energy rating for the house. Energy ratings go from A to G,
A being the most energy efficient and G being the least energy efficient.