Conversion of propane heating system to electricity
LM Wind Power, 2018
3E Eng. has been mandated by LM Wind Power to estimate the benefits of different scenarios for converting the propane heating system at its Gaspé plant and to issue the associated recommendations. In this study, two heating system conversion scenarios were studied:
- Conversion of the heating system to a 100% electric system
- Conversion of the dual-energy heating system to electricity and propane
To do this, energy consumption and power for heating of industrial site was modeled on a monthly basis. Costs were estimated based on Hydro-Québec’s current pricing.
A 100% electric system would save about 14% of heating costs. In this scenario, the cost of the minimum power of Hydro-Québec’s bill becomes very high. Indeed, an increase in peak power over a short period of time for heating in winter increases the minimum power to be charged for the rest of the year. For example, in this scenario, if the minimum temperature for the coldest day of winter increased from -17 to -22 degrees Celsius, the conversion savings would increase from 14% to 7% of heating costs.
A dual-energy system with electricity and propane would save about 21% of heating costs. In this scenario, the electrical system would provide basic heating and the propane system would be used to meet the spikes. Thus, the weather conditions would have much less impact on the minimum power to be charged. This scenario also reduces project costs because the capacity of the required electric heating system is significantly less (reduction of about 35% of the maximum capacity required).
Both scenarios would be eligible for a major grant from the EcoPerformance. For small and medium-sized consumers, the amount of the subsidy granted would be the minimum of the following amounts:
- 75% of project costs
- Amount required to bring the return period on investment to 2 years
- $125/t CO2e for up to 10 years
A dual-energy heating system could also be used to participate in the Hydro-Québec power demand management program. Under this program, Hydro-Québec offers a $70/kW financial incentive to reduce the power call for certain periods of between three to four hours. The participant is previously notified of these periods by Hydro-Québec. For example, an average reduction in the 200 kW peak for all periods in a year could result in a $14,000 incentive.
An interesting alternative scenario that was not considered in this study is a biomass heating system conversation.
About Hydro-Québec’s power to charge
The power to be charged is the highest of the values between:
- Active power
- 90% of apparent power
- Minimum power
Active power is defined by the maximum power called in the consumption period over a 15-minute integration period (e.g., a period where there would be a very high demand for heating coinciding with a high demand for process). Minimum power represents 65% of the maximum active power of the previous winter months (December, January, February, March).
Thus, in a scenario where a building is heated with electricity, the coldest day of the year could have a significant impact on the power to be charged for the entire year. For example, if the maximum active power of a winter month is 3,000 kW, the minimum power will be 1,950 kW. If the actual power from April to November is less than 1,950 kW, the minimum power is still charged.