EE FORUM JULY 2014 • MAIN TOPIC – CHANGE TO TOU TARIFF, THE CAVENDISH EXPERIENCE • CONCLUSION – AN INSIGHT INTO FUTURE ENERGY SAVING INITIATIVES FOR CAVENDISH CHANGE TO TOU TARIFF – WHY? • Very Large Power User tariff falling away in July 2011 • Choice between two tariffs – LPU (MV) & TOU • TOU tariff offered the opportunity to be pro-active about load management in order to further save on electricity costs • TOU tariff offered a cheaper kWh rate vs VLPU or LPU (MV) tariffs during standard and off-peak times for 9 months of the year • TOU tariff peak time only constitutes approximately 27% of retail operating hours during the week and 0% over weekends, which is the peak operating time for retail with kWh consumption at its highest • For retail, the kWh consumption is at its lowest during the 3 winter months due to reduced HVAC loads, which constitutes the high season for the TOU tariff • Reduce operating costs for the centre and combat high electricity tariff increases CHANGE TO TOU TARIFF – COST ANALYSIS AND CALCULATIONS TO INFORM DECISION • Compared LPU (MV) tariff vs VLPU tariff to calculate the variance in cost • Compared TOU tariff vs VLPU tariff to calculate the variance in cost • LPU (MV) tariff was slightly easier due to bulk kWh and kVA figures being readily available from Council bills • TOU was harder due to MV bulk metering data not being available for Cavendish for the purposes of calculating TOU kWh figures CHANGE TO TOU TARIFF – COST ANALYSIS AND CALCULATIONS TO INFORM DECISION • Results for LPU (MV) vs VLPU tariff – pay R700k more for electricity p.a. mainly due to VLPU low kVA charge (almost half) • Calculation for TOU figures - typical week load profile for Cavendish and applied % for off peak, standard and peak kWh consumptions for high and low seasons • Results for TOU vs VLPU tariff – pay R70k less for electricity p.a. due to TOU having lower kVA and service charges CHANGE TO TOU TARIFF – COST ANALYSIS AND CALCULATIONS TO INFORM DECISION City of Cape Town: Draft Electricity Tariffs To Be Implemented With Effect From 1 July 2011 Average 19.94 % Increase (All values exclude VAT) Commercial Tariffs Large Power MV Very Large Power Time of Use 2010/11 2011/12 %Incr Service R/Day 23.90 28.67 19.96 Energy c/kWh 37.85 45.40 19.95 Demand R/kVA 112.69 135.16 19.94 Service R/Day 5000.00 n/a n/a Energy c/kWh 37.85 n/a n/a Demand R/kVA 69.95 n/a n/a Service R/day 3900.00 4680.00 20.00 Energy High-Peak c/kWh 191.88 230.14 19.94 High-Standard c/kWh 50.74 60.86 19.94 High-Off Peak c/kWh 27.62 33.13 19.95 Low-Peak c/kWh 54.48 65.34 19.93 Low-Standard c/kWh 33.80 40.54 19.94 Low-Off Peak Demand c/kWh R/kVA 23.97 60.87 28.75 73.00 19.94 19.93 Notes to the TOU Tariff: High Demand season is from June to August, Low Demand season is from September to May. Hours of Operation: Peak Standard Off Peak Weekdays 07:00 to 10:00, 18:00 to 20:00 Weekdays 06:00 to 07:00, 10:00 to 18:00, 20:00 to 22:00 All other times Note also that demand is only measured during the Peak and Standard periods, and not off peak times, and that public holidays are considered normal days due to metering constraints. CHANGE TO TOU TARIFF – CHALLENGES TO EFFECT THE CHANGE IN TARIFF • New meter installation – co-ordination between the electricity department and metering department • Getting the correct documentation from the City as well as getting signatures • Deposit that became applicable according to the max allowable demand, that was not applicable in the past • Timeline for change to TOU tariff from date of first application – 8 to 9 months CHANGE TO TOU TARIFF – ACTUAL RESULTS FROM FIRST YEAR OF TOU IMPLEMENTATION • First year of measurement was from Feb to Dec 2012 • With the VLPU tariff no longer applicable, the comparison turned to TOU vs LPU (MV) • For 11 months in 2012, Cavendish saved R177k by being on the TOU tariff CHANGE TO TOU TARIFF – ACTUAL RESULTS FROM FIRST YEAR OF TOU IMPLEMENTATION 50 45 40 35 30 % Off-peak kWh's 25 % Standard kWh's % Peak kWh's 20 15 10 5 0 February March April May June July August September October November December CHANGE TO TOU TARIFF – LEARNINGS AND IMPROVEMENTS FROM FIRST YEAR OF TOU IMPLEMENTATION • • • • • Budgets had to be changed to accommodate the winter high season as the electricity cost increased dramatically – between 50 to 80% Even though Cavendish saved money in 2012 by being on the TOU tariff vs the LPU (MV) tariff, more could be done to reduce electricity costs There is a balance that needs to be struck between saving energy and compromising your centre e.g. turning off lights during the winter high season More energy saving initiatives means less kWh’s during peak time hours (high and low season): – lighting energy saving initiatives implemented – renewable energy saving initiatives implemented More investigation would have to go into HVAC efficiency and reducing kWh’s during the winter high season especially: – major maintenance of HVAC equipment to be conducted before June to ensure optimal operational efficiency of equipment during the winter months – Maximise free cooling from outside air temperature conditions – Try to start HVAC plant (chillers, cooling towers) only after the morning peak time period – Increase chilled water set point temperature by 1 or 2 degrees – Increase diffuser temperature set points by 1 or 2 degrees CHANGE TO TOU TARIFF – ACTUAL RESULTS FROM SECOND YEAR OF TOU IMPLEMENTATION • Second year of measurement was from Jan to Dec 2013 • For 12 months in 2013, Cavendish saved R253k by being on the TOU tariff CHANGE TO TOU TARIFF – ACTUAL RESULTS FROM SECOND YEAR OF TOU IMPLEMENTATION 50 45 40 35 30 25 20 15 10 5 0 % Off-peak kWh's % Standard kWh's % Peak kWh's CHANGE TO TOU TARIFF – ARE WE IMPROVING? Graph of variance between TOU and LPU (MV) in 2013 (Rands) % Variance between TOU and LPU (MV) - 2012 % Variance between TOU and LPU (MV) - 2013 -20 December November October September August -10 July 0 June 0 May 10 April 10 March 20 February 20 % Variance between TOU and LPU (MV) 2012 -10 -20 -30 -30 -40 -40 -50 -50 January February March April May June July August September October November December Graph of variance between TOU and LPU (MV) in 2012 (Rands) % Variance between TOU and LPU (MV) 2013 CHANGE TO TOU TARIFF – CAN IT WORK FOR RETAIL ENVIRONMENTS? • YES, IT HAS CERTAINLY BENEFITTED CAVENDISH • HOWEVER, CONSIDERATION MUST BE GIVEN TO THE DYNAMICS OF YOUR CENTRE – LOAD PROFILE, ABILITY TO SAVE MAXIMUM ENERGY DURING WINTER HIGH SEASON MONTHS AN INSIGHT INTO FUTURE ENERGY SAVING INITIATIVES FOR CAVENDISH AN INSIGHT INTO FUTURE ENERGY SAVING INITIATIVES FOR CAVENDISH Trial voltage optimisation system • Guaranteed savings – 123700kWh’s p.a. & 46kVA p.m. for a 1 MVA VO unit • ROI – 4 years AN INSIGHT INTO FUTURE ENERGY SAVING INITIATIVES FOR CAVENDISH Replacement of T5 flourescents with LED alternative • Anticipated savings – 868517kWh’s p.a. & 112kVA p.m. • ROI – 58 months AN INSIGHT INTO FUTURE ENERGY SAVING INITIATIVES FOR CAVENDISH Solar and wind QUESTIONS? THANK YOU