Heating
CO2-emission by heating
The heating of buildings usually puts a strain on the climate. This is unavoidable as nobody wants to freeze. But the heating can be done more or less efficiently, and that makes a difference. The burning of fossil fuels causes CO 2 emissions. Emission factors indicate how much carbon dioxide is generated by the consumption of one kilowatt hour (1 kWh) from a certain energy source. This includes everything involved in the provision of the energy; i.e. the winning and transport of the fuels, the conversion steps (which also require energy), and the actual use on site. This results in the following diagram:
| 1 kWh heat energy made of... | equals... | and leads to the following CO2-emissions... |
|---|---|---|
| natural gas | 0,11 m3 |
0,21 kg |
| crude oil | 0,10 l |
0,29 kg |
| district heating (average) | 0,16 kg |
|
| hard coal | 0,12 kg |
0,35 kg |
| brown coal | 0,18 kg |
0,42 kg |
Heating installation
Schools today are normally heated with gas or oil boilers or with district heating. However, special model schools are also heated with wood. Carbon dioxide emissions are very low since carbon dioxide is stored in wood when it grows. The CO 2 then escapes when it is burnt. In addition, no one needs to shovel wood! These systems normally use wood chips that automatically slide into the boiler. Concerning conventional heating systems and climate protection, district heating is the best solution, but it should be heating from a co-generation plant. In this type of plant, power and heat are generated together with a highly effective method using one fuel (usually gas). There are no high levels of heat loss as in large power plants, and the heat that is emitted is used for district heating. The next best possibility is the use of gas in a modern condensing boiler. Where conventional chambers release exhaust into the chimney at a temperature of about 160 degrees Celsius, the condensing boiler uses the heat from the exhaust as well as the heat from the steam condensation so that the exhaust is only 40 to 60 degrees Celsius. This increases the effectiveness of natural gas approximately about 10 percent. Condensation usage is also possible with crude oil, but the increase in effectiveness is only about 5 percent.
Regulating
It is not a good idea to switch off the heat completely at night, because the building does not reach the comfort level until the next morning. However, it is practical to lower the heat at night, so that the rooms only drop from a daytime temperature of about 20 degrees to about 16 degrees Celsius. This is called the setback temperature. If the room heating starts at the right time in the morning (usually 1 to 2 hours before school starts), then it is warm again when classes start and, at the same time, heat energy has been saved. The heat regulator is responsible for the setback temperature. This requires special attention.
In the worst case, there is no regulator and the heater either heats the whole school building or not. However, this is rare. Normally, various sections of the building can be heated independently. In a perfect case scenario, there is a timer-controlled multitude of heating circuits in one building which ensures that only the actually used sections are heated. Modern regulators are computer-controlled and can be programmed to adhere scheduled usage times, even during the holiday. This is proper heating based on need. Check the programming regularly. Usage times in schools often change without the regulators being reset. Efficient schedule programming could possibly shorten heating times.
In some cases, the caretaker cannot access the regulator. It is often controlled by the structural engineering office where temperatures and times can be monitored centrally. In this case, try to contact the responsible person to coordinate usage times.
Function of the thermostat valve
Each classroom is generally equipped with heater valves to regulate the heating. These are normally thermostat valves. These valves may look like on/off switches, but they do much more than that. A thermostat valve regulates the heating so that a pre-set room temperature is reached or maintained.
The thermostat valve contains a thermometer that opens or closes the heater valve. It can correctly regulate the heater when it is surrounded by the air in the room. Therefore, it is highly important to close the thermostat valves completely while the room is aired thoroughly. If cold external air hits the thermostat, the heater valve is opening automatically to heat up the "cold" room.
Proper ventilation
After turning off the thermostat valve open all windows and doors to ventilate completely. It is recommended to replace the used room air as fast as possible to prevent the furniture and walls of cooling. After 1 to 5 minutes (depending on wind and temperature), close the doors and windows again and return the thermostat valves to their initial settings.
If the classroom is ventilated through continuously tilted windows, there won't be suitable exchange of fresh and used air. Moreover, as soon as the cold external air hits her thermostat valve it opens and the heater rewarms. Thus further windows have to be opened.
