1. Case application: Variable Speed Drive in Industry, Spain
IEA-DSM TASK XXI: Standardisation of Energy Savings Calculations
Case application: Variable Speed Drive in Industry, Spain
Alejandro Ruiz Davia
Workshop: Harmonization in Energy Savings Calculation: How To Fit International Experiences With Korean Practice, Now And In The Near Future
Seoul, 21 April 2011

2. TASK XXI: Standardisation of Energy Savings Calculations
Summary of the program
Objectives: to obtain a significant reduction in electrical consumption in industrial pumping, ventilation and air compressed systems in an economical way
Estimation of savings before installation: not standardized although this document is based upon common engineering calculations
Sectors: industrial sector, specially the chemical/process industry
Incentives: the installation of VSD systems is subsidized with up to 22% of the investment

3. Technologies involved
TASK XXI: Standardisation of Energy Savings Calculations
Technologies involved
How it works? The Variable Speed Drive adjusts the power output of these devices and thus, the flow, depending of the actual demand in the installation
State of technology: This is a proven and mature technology and can result in significant savings in system with variable loads
Demand Response effect? VSD can lower the load curve, but it cannot be considered as a controllable measure, since it depends of factors beyond control of the grid operator

4. Annual Net Energy Savings
TASK XXI: Standardisation of Energy Savings Calculations
Annual Net Energy Savings
Energy savings to be determined will consider:
percentage of motors in which the application of VSDs is cost-effective in each surveyed industrial sector
number of electric motors per industrial sector, application and power ranges
percentage of energy saving in industrial pumping, ventilation and air compressed processes using VSD
average power of the electric motors to be changed
number of operating hours, to be corrected with the market penetration of the VSD in industrial sectors

5. Formula and parameters
TASK XXI: Standardisation of Energy Savings Calculations
Formula and parameters
j: Industrial Sector: Food, beverage and tobacco, Paper and cardboard, Basic quemistry, Iron and steel
i: Type of application: Pumps, Fans, Air compressors
KSpain: Correction factor Spain vs. Europe
Kij: Percentage of motors in which the application of VSDs is cost-effective in each surveyed industrial sector
Nj: Number of electric motors per industrial sector, application and power ranges
Paverage: Average power (kW) by power range (kW)
%ESi: Percentage of energy savings as an average by type of application
hij: Number of operating hours per industrial sector, application and power ranges

6. TASK XXI: Standardisation of Energy Savings Calculations
Formula application
Considering the data from the report ”Improving the Penetration of Energy-Efficient Motors and Drives1”, and applying a correction factor for Spain, the savings achivied with VSD for the four industries proposed (Food, beverage and tobacco, Paper and cardboard, Basic quemistry, Iron and steel) can be estimated:
Food
Paper
Basic chemistry
Iron Steel
Total Savings
Yearly energy savings in Spain (MWh)
This GWh corresponds to approximately 1% of total energy consumption in Spain
Source: ISR – University of Coimbra (Portugal)

7. TASK XXI: Standardisation of Energy Savings Calculations
Adjustments
Baseline: The baseline is the energy consumed before the application of the measure and is considered to be static
Gross to net corrections: There are no significant interactions to be considered
Normalization: There is no need for normalization as there are no influence variables
Lifetime: The expected lifetime of a VSD is infinite, during its lifetime there should not be an appreciable reduction in performance

8. In this example, GHG savings are estimated around 731 kTn of CO2
TASK XXI: Standardisation of Energy Savings Calculations
GHG savings
The only GHG relevant is CO2, the savings are determined by applying the emissions factor to the energy savings
Each kWh consumed in Spain (using as reference data from REE, and evaluated in accordance to the European Commission Directive 2007/589/CE) amounts to 0,360 kg of CO2, thus, the global annual savings are:
In this example, GHG savings are estimated around 731 kTn of CO2

9. TASK XXI: Standardisation of Energy Savings Calculations
References
ASHRAE: American Society of Heating, Refrigerating and Air-Conditioning Engineers  
IDAE: Institute for Diversification and Saving of Energy
REE: Red Eléctrica de España, Electrical System Operator
EUROSTAT: European Comission Statistic Programme
STUDY: IMPROVING THE PENETRATION OF ENERGY- EFFICIENT MOTORS AND DRIVES - EU project coordinated by ISR-University of Coimbra

10. IEA-DSM TASK XXI: Standardisation of Energy Savings Calculations
Questions?