Author. František Sás, Director of Energy Controlling and Support Activities ENGIE Services
Bratislava, 12 October 2020
ENGIE in Slovakia launched a pilot project to test the NODA system during the 2018/2019 heating season. This system was deployed in the thermal management in Pezinok. The aim of the project is to optimise heat production and distribution, optimise the fuel mix and reduce fuel and operating costs. Two heating seasons of operation have produced measurable positive results.
What is NODA?
A tool that combines classical engineering with modern IT technologies and algorithms. It is used for:
– performance optimization in heating system,
– data collection and analysis,
– production – distribution – consumption interconnection,
– integration with SCADA system,
– visualization of parameters and measured variables. NODA uses big data, consumption, power and weather forecasting and machine learning algorithms for its operation. All these features allow to achieve the set main goals, namely optimization of heat production and distribution, increase of energy efficiency and last but not least cost reduction. NODA performs all its tasks in real time. Both data collection and individual interventions in the operation of the plant in Pezinok.
ENGIE pilot test programme in Slovakia
ENGIE’s parent company chose Slovakia for its pilot project because it wanted to test the system in a dual-fuel (biomass and natural gas) thermal power plant (TH). And it was the TH in Pezinok that met all the parameters and requirements that were necessary for the successful deployment and verification of this intelligent system. The requirements for the pilot project, in addition to the dual-fuel base, included automated data collection with a readout period of at least 15 minutes, communication via the UA-OPC interface (OPC Unified Architecture / M2M – machine to machine communication) and communication with the SCADA system. Another, equally important part of the whole project was the addition of interior temperature sensors in selected apartments in Pezinok. The purpose of this project was to test the control and optimization of the operational load in the CZT network with active use of the thermal inertia of the buildings. In order to achieve the objectives, two strategies were used during the pilot operation aimed at reducing primary energy use:
- Reduction of gas consumption when starting gas boilers,
- optimising the use of biomass boilers by using “virtual storage”, which expanded the capacity of the storage tanks.
The supplied objects and the heat distribution systems themselves are used as “virtual storage”. Based on weather forecasts, heat is stored in or extracted from them. All in order to maximise the use of renewable energy sources.
What are the results?
Figure 1 shows the primary energy use during the previous 3 heating seasons. Figure 2 then shows the primary energy use in terms of dayrates. Figure 2 shows that when comparing the 2019/2020 heating season with the 2017/2018 heating season, when the NODA system was not yet deployed, there was a 13.7% decrease in primary energy use.
Figure 1
Figure 2
Figure 3 shows a comparison of the distribution of primary energy use (gas/biomass) in terms of day-use, by month, over the last 3 heating seasons. The figure shows that in the last heating season there has been a ‘smoothing’ of the primary energy consumption in daily units. It should also be added that in the period 08/2020 – 09/2020, minor adjustments were also made directly to the connection of the boilers and heat storage tanks based on the findings.
Figure 3
All the changes made, combined with the use of NODA to optimise performance, have also produced results in the overall efficiency of the CHP system, as can be seen in Figure 4. When comparing the 2019/2020 and 2017/2018 heating seasons, an increase of almost 11% is evident. To determine the overall efficiency of the CHP system, the readings from the heat meters at the consumption points, the fuel consumption (natural gas, biomass) and the calorific value of the fuel were used. The overall efficiency of the system includes the efficiency of the boiler house, the primary distribution system and the OST.
Figure 4
Successful testing yielded positive results
Testing of the NODA system in Pezinok was successful and revealed an interesting potential for the use of modern technology in CZT supply systems.
The 2019/2020 heating season produced the following findings:
- The optimisation of gas consumption showed primary energy savings totalling 79 MWh, equivalent to approximately 8% of natural gas consumption.
- The optimisation of biomass consumption showed a total saving of 95 MWh, which corresponds to approximately 2% of biomass consumption.
- The total amount of savings for the CZT system in Pezinok is 174 MWh per heating season, which corresponds to savings of approximately 2.8%.
The positive results of the pilot programme confirmed that the use of NODA is particularly suitable for larger central heating supply circuits.