The COVID-19 pandemic continues to wreak havoc on global operations and economies. Inadvertently, lock- downs and working from home have reduced the daily carbon footprints of transport and oce buildings. A bene cial consequence of these reductions is the ability to measure the di erential demand of occupants, to benchmark the base load of these buildings, and identify opportunities for eciency improvements. In this paper we evaluate the change in energy demand in ve public schools in South Africa with changes in occupancy due to the COVID-19-imposed lockdowns. Keywords: School electricity; Energy usage; Smart meter; School energy pro les; COVID-19; Pandemic; School responses 1. Introduction South Africa's public (non-private) schools face many challenges, especially budgetary constraints, and even more so for schools in the lower four of the ve auence quintiles [1]. These budgetary constraints are compounded by the rising cost of water and energy, of which schools are heavy and often wasteful users [1{3]. Given the lack of nancial resources in the educational domain and the troubled state of basic education in the country, any 5 reduction in wasteful expenses could be put to good use, for example to help to to pay teacher salaries or invest in educational infrastructure. Since the country's predominant source of energy is electricity generated by its state- owned behemoth, Eskom, burning fossil fuels by, any reduction in usage also results in a reduction in greenhouse emissions. One of the unintended consequences of the COVID-19 pandemic's lockdowns has been a reduction in greenhouse 10 emissions, albeit temporarily [4]. This reduction was driven by the lower energy requirements in large oce buildings and also by diminished transportation requirements as people worked from home. Moreover, as economic activity subsequently slumped, energy consumption reduced further, with commensurate reductions in the environmental impact [4]. The pandemic also provided an opportunity to evaluate the nexus and resulting consequences of the pandemic, energy systems and climate change [5]. 15 The South African government have responded to the pandemic with a focus on provision of healthcare capacity and short-term scal interventions to counter the multi-sectoral decline in economic activity. With regards to the education sector, school closures were implemented, due to lockdown regulations, and measures were taken to ensure learner education could proceed safely as far as practically possible [6]. Similar to large oce blocks, a reduction was expected in schools' energy usage with unoccupied or partially 20 occupied schools. However, with children out of school and e ectively being home-schooled, and with employment uncertainty, some parents were either unable or unwilling to pay school fees. In some instances, teachers, support and other (i.e. administrative) sta had to be laid o , especially when their salaries were paid by the governing board and therefore dependent on the payment of parents' contributions. 1.1. Schools in South Africa and their COVID-19 response 25 Each of South Africa's nine provinces has a dedicated education department guided by the national education ministry. The provincial education departments are responsible for public schooling for grades grades R to 12. South Corresponding author Email address: mjbooysen@sun.ac.za (M.J. Booysen) Preprint submitted to Energy for Sustainable Development May 17, 2021 Table 1: COVID time table 2020 Dates Description Level Ref 18 March Schools closed early due to COVID-19 in country { [11] 19 March Regulation 6 - closure of schools until April 15th (eventually the 1st of July) { [12] 26 March National lockdown Level 5 for 21 days 5 [13] 9 April Two-week extension on 21-day Lockdown 5 [14] 1 May National lockdown Level 4 lockdown 1st of May. Phased re-opening of schools to be provided.5 [15] 13 May Need for re-organisation of schools stated 4 [16] 24 May Resumption of classes for grades 7 and 12 learners planned for 1 June 4 [17] 29 May National lockdown Level 3 4 [18] 1 June School reopening postponed. Sta could report to work on 1 June. 3 [19] 25 June Provisional reopening of school at 50% capacity announced with move to digital platforms. Grade R, 1, 2, 3, 6, 10 and 11 to return 6th of July.3 [20] 12 July Call to increase ventilation in schools. 3 [21] 23 July Reopening of schools. Grade 7 and 12 returned on the 8th of June. On 6 July grades R, 6 and 11 returned. However, schools closed between 27 July and 24 August.3 [22] 17 Aug National lockdown Level 2 2 [23] 20 Sep National lockdown Level 1 1 [24] Africa's public schools are categorised into ve quintiles based on the auence of the surrounding areas, where one is least auent and ve is most auent. Quintile four and ve schools constitute fee-paying schools, whose parents contribute nancially towards the school's funds through fees. Quintile three schools tend to be fee-paying, however these schools are situated in poorer communities. Quintile one and two schools constitute no-fee schools, whose parents are considered too poor to contribute to school funds through fees. The government contribute more per 5 student for poorer schools. Covid-19 induced lockdowns in South Africa meant that the movement of citizens and normal day operations of the public and private sectors were restricted with the exceptions of health services. There were levels to the lockdowns ranging from level 5 to level 0 - decreasing in restrictions and freedom of movement. During the Level 5 lockdowns (the most restrictive stage of lock down due to COVID { discussed in detail in 10 section1.2), schools were also closed, with learners reverting to remote learning [7, 8]. Despite being met with some opposition, they eventually reopened with social distancing enforced. Initially, this resulted in partial occupancy, as temporary revised education plans were adopted { learners attended schools every second or third day, and well-resourced schools could use blended learning. Furthermore, mobile classrooms were used by the Western Cape Education Department (WCED) to allow schools to operate with 1.5m physical separation, which reduced classrooms 15 to partial capacity. Similar to non-educational buildings, this partial occupancy due to physical distancing was expected to have an impact on the building energy usage [9]. Changes in energy uses could be due to factors such as changes in occupancy of students and sta , usage of items, and COVID-induced arrangements (i.e. the usage of more classrooms due to social distances, phased re-opening of schools, and added ventilation in classrooms etc.). All of these factors could impact electricity usage, savings and carbon emissions of the schools. Additionally, ZAR 50 20 million were assigned to the manufacturing of 100 mobile classrooms. Although these additional classrooms could have had the intended consequence of an increase in the electricity usage in schools [10], none of the schools in our sample had mobile classrooms recently added. 1.2. An education-focused COVID-19 timeline This section presents a timeline of events relevant to COVID-19 in South Africa, and speci cally includes events 25 relevant to the education system. The main events, listed in Table 1, were used to assess the possible in uences on electricity usage in schools and will be correlated with measurements at the schools in our sample set. Only the rst-wave levels of lockdown are shown. The dates of lockdown levels are shown where the country went into isolation with strict rules from the 23 March 2020 for a month, this was level ve lockdown - schools were closed until the 1st of May. Level four saw schools re-opening in phases, only grade 12 of the secondary school grades 30 and the senior primary school grade (i.e. grade 7) returned to school from the 1st of June 2020. The move to level three of lockdown was announced on the 29th of May 2020. This meant for the phasing in of the rest of the grades which includes primary school grades R, 2, 3 and 6 and secondary school grades 10 and 11 on the 6th of July. On the 12th of July, there was a call to increase the ventilation in schools, which may have increased impacts of electricity usage. The schools were closed again from the 27th of July until the 24th of August 2020. Thereafter, 35 the move to level two of lockdown followed, which saw schools continue their schooling until the December break. 2 COVID-19 measures were maintained for the safety of the learners and sta . The e ects of level one lockdown was also evaluated. In our article we correlated these events with our schools' energy data. 1.3. Holidays of South African schools Due to the pandemic term dates varied substantially from 2019 to 2020 [25]. The school term dates and holidays are shown in Table 2, and highlighted clearly in the gures in the results section. These lockdown-imposed school 5 closures were from 18 March to 1 June and from 27 July to 24 August of 2020. 2019 2020 Term 1 09 Jan { 16 Mar 15 Jan { 21 Mar Term 2 02 Apr { 15 Jun 08 Jun { 25 Jul Term 3 09 Jul { 21 Sep 24 Aug { 24 Oct Term 4 01 Oct { 7 Dec 02 Nov { 16 Dec Table 2: School term dates 1.4. Related work COVID-19 has availed opportunities for research, especially energy research. In the special issue by Sovacool et al. [5] on energy research during the rst part of COVID-19, more clarity is sought that links COVID-19, energy and climate that might have lead to known and anticipated impacts, amongst other relevant topics. This overarching 10 research spectrum helps to give context to the impact of the pandemic. Regarding research on electricity transition, the pandemic has brought opportunities to still focus on climate change - bringing a window to accelerate, to learn and make society more resilient, without disregarding the devastating e ects experienced by the world-wide [26]. However, there are at this stage few research outputs from Africa or in an African context with regards to the impact of COVID-19 on energy systems. Addressing the current lack of research on COVID-19 impact in an 15 African context is a great priority due to the need for science-based evidence in decision and policy-making. The African contribution was a mere 0.6% of the global research output with South Africa contributing eight out of 22 COVID-19-related contributions. COVID-19 a ected many important sectors in South Africa and globally, which had an impact on energy usage. These sectors included the health [27, 28], food [29], environmental [30{32] and economic sectors [33, 34]. The manner in which these sectors were a ected also had in uence on the energy sector 20 due to COVID-19 regulations [35{40]. Therefore, there is a need to evaluate the e ectiveness of the lockdown measures in the South African context [41], especially in terms of energy. 1.5. Contribution In this paper we assess the impact of COVID-19 restrictions on school energy usage and quantify the nancial savings and environmental impact of these changes. The assessment was done to understand the impact of occupancy 25 on the energy requirements of a school (the delta), and also to quantify base load demand, which could be used to identify untapped potential for savings in aging buildings [42]. We focus on ve schools in Stellenbosch, in Western Cape province of South Africa and their energy usage during the pandemic compared to the preceding 12 months. 2. Method We used a mixture of smart-meter data and bills to evaluate the change in energy (electricity) usage at the ve 30 schools in Stellenbosch. Table 3 shows information about the schools included in the energy analysis. The time periods analysed were from November 2018 to October 2019 and November 2019 to October 2020. In addition to the energy impact, we assessed the impact of the lockdowns on the cost of this electricity. Although a reduction in electricity costs reduced expenses, we also had anecdotal evidence of parents stopping to pay school fees, o setting reductions in electricity expenses. We therefore obtained two years' fee contributions from three schools, two quintile 35 ve schools and one quintile four school, to assess changes in contributions. To determine the the electricity usage of the schools we used two methods. The Stellenbosch council's smart meters that are used for billing were used to measure usage in 30-minute intervals over a two-year period from November 2018 to November 2020. This data was also used to determine the cost of the electricity usage, as the schools were on Time-of-Use tari s. These costs were cross-validated with monthly electricity bills over the same 40 two-year period. 3 Table 3: Summary of the ve schools in our energy data set Primary/Secondary Quintile No of pupils Size of building [m2] Hostel (Y/N) (School 1) Primary 5 600 9,731 N (School 2) Primary 5 800 6,894 N (School 3) Secondary 5 720 10,613 Y (School 4) Secondary 5 550 7,609 Y (School 5) Secondary 4 1,200 12,132 N /uni0000002d/uni00000044/uni00000051 /uni00000029/uni00000048/uni00000045 /uni00000030/uni00000044/uni00000055 /uni00000024/uni00000053/uni00000055 /uni00000030/uni00000044/uni0000005c /uni0000002d/uni00000058/uni00000051/uni00000048 /uni0000002d/uni00000058/uni0000004f /uni00000024/uni00000058/uni0000004a /uni00000036/uni00000048/uni00000053 /uni00000032/uni00000046/uni00000057 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 /uni00000036/uni00000046/uni0000004b/uni00000052/uni00000052/uni0000004f/uni00000003/uni00000017/uni00000003/uni00000015/uni00000013/uni00000014/uni0000001c/uni00000036/uni00000046/uni0000004b/uni00000052/uni00000052/uni0000004f/uni00000003/uni00000016/uni00000003/uni00000015/uni00000013/uni00000015/uni00000013 /uni00000036/uni00000046/uni0000004b/uni00000052/uni00000052/uni0000004f/uni00000003/uni00000017/uni00000003/uni00000015/uni00000013/uni00000015/uni00000013 (a) /uni0000002d/uni00000044/uni00000051 /uni00000029/uni00000048/uni00000045 /uni00000030/uni00000044/uni00000055 /uni00000024/uni00000053/uni00000055 /uni00000030/uni00000044/uni0000005c /uni0000002d/uni00000058/uni00000051/uni00000048 /uni0000002d/uni00000058/uni0000004f /uni00000024/uni00000058/uni0000004a /uni00000036/uni00000048/uni00000053 /uni00000032/uni00000046/uni00000057 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 /uni00000036/uni00000046/uni0000004b/uni00000052/uni00000052/uni0000004f/uni00000003/uni00000015/uni00000003/uni00000015/uni00000013/uni00000014/uni0000001c /uni00000036/uni00000046/uni0000004b/uni00000052/uni00000052/uni0000004f/uni00000003/uni00000018/uni00000003/uni00000015/uni00000013/uni00000014/uni0000001c/uni00000036/uni00000046/uni0000004b/uni00000052/uni00000052/uni0000004f/uni00000003/uni00000014/uni00000003/uni00000015/uni00000013/uni00000015/uni00000013 /uni00000036/uni00000046/uni0000004b/uni00000052/uni00000052/uni0000004f/uni00000003/uni00000015/uni00000003/uni00000015/uni00000013/uni00000015/uni00000013 /uni00000036/uni00000046/uni0000004b/uni00000052/uni00000052/uni0000004f/uni00000003/uni00000018/uni00000003/uni00000015/uni00000013/uni00000015/uni00000013 (b) /uni0000002d/uni00000044/uni00000051 /uni00000029/uni00000048/uni00000045 /uni00000030/uni00000044/uni00000055 /uni00000024/uni00000053/uni00000055 /uni00000030/uni00000044/uni0000005c /uni0000002d/uni00000058/uni00000051/uni00000048 /uni0000002d/uni00000058/uni0000004f /uni00000024/uni00000058/uni0000004a /uni00000036/uni00000048/uni00000053 /uni00000032/uni00000046/uni00000057 /uni00000003/uni00000013/uni00000018/uni00000013/uni00000014/uni00000013/uni00000013/uni00000014/uni00000018/uni00000013/uni00000015/uni00000013/uni00000013/uni00000015/uni00000018/uni00000013/uni00000030/uni00000052/uni00000051/uni00000057/uni0000004b/uni0000004f/uni0000005c/uni00000003/uni00000045/uni0000004c/uni0000004f/uni0000004f/uni00000056/uni00000003/uni0000003e/uni0000003d/uni00000024/uni00000035/uni00000003/uni00000057/uni0000004b/uni00000052/uni00000058/uni00000056/uni00000044/uni00000051/uni00000047/uni00000040/uni00000036/uni00000046/uni0000004b/uni00000052/uni00000052/uni0000004f/uni00000003/uni00000016/uni00000003/uni00000015/uni00000013/uni00000014/uni0000001c /uni00000036/uni00000046/uni0000004b/uni00000052/uni00000052/uni0000004f/uni00000003/uni00000017/uni00000003/uni00000015/uni00000013/uni00000014/uni0000001c/uni00000036/uni00000046/uni0000004b/uni00000052/uni00000052/uni0000004f/uni00000003/uni00000016/uni00000003/uni00000015/uni00000013/uni00000015/uni00000013 /uni00000036/uni00000046/uni0000004b/uni00000052/uni00000052/uni0000004f/uni00000003/uni00000017/uni00000003/uni00000015/uni00000013/uni00000015/uni00000013 (c) /uni0000002d/uni00000044/uni00000051 /uni00000029/uni00000048/uni00000045 /uni00000030/uni00000044/uni00000055 /uni00000024/uni00000053/uni00000055 /uni00000030/uni00000044/uni0000005c /uni0000002d/uni00000058/uni00000051/uni00000048 /uni0000002d/uni00000058/uni0000004f /uni00000024/uni00000058/uni0000004a /uni00000036/uni00000048/uni00000053 /uni00000032/uni00000046/uni00000057 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 /uni00000036/uni00000046/uni0000004b/uni00000052/uni00000052/uni0000004f/uni00000003/uni00000015/uni00000003/uni00000015/uni00000013/uni00000014/uni0000001c /uni00000036/uni00000046/uni0000004b/uni00000052/uni00000052/uni0000004f/uni00000003/uni00000018/uni00000003/uni00000015/uni00000013/uni00000014/uni0000001c/uni00000036/uni00000046/uni0000004b/uni00000052/uni00000052/uni0000004f/uni00000003/uni00000014/uni00000003/uni00000015/uni00000013/uni00000015/uni00000013 /uni00000036/uni00000046/uni0000004b/uni00000052/uni00000052/uni0000004f/uni00000003/uni00000015/uni00000003/uni00000015/uni00000013/uni00000015/uni00000013 /uni00000036/uni00000046/uni0000004b/uni00000052/uni00000052/uni0000004f/uni00000003/uni00000018/uni00000003/uni00000015/uni00000013/uni00000015/uni00000013 (d) Figure 1: Energy usage between 2018/2019 and 2019/2020, monthly aggregated for schools with hostels (a) and schools without (b). Monthly bills between 2018/2019 and 2019/2020, schools with hostels (c) and schools without (d) 3. Results 3.1. Energy usage analysis Figure 1 shows the monthly usage and bills of schools during 2019 and 2020 for both schools with hostels, in Figure 1 (a) and (c), and schools without hostels, in Figure 1(b) and (d). These results clearly demonstrate substantial reductions in usage from April 2020, when the country went into lockdown and schools closed. When 5 compared to 2019, the average monthly reduction from April to October was 33 % for schools with hostels, and 25 % for schools without hostels. These reductions are substantial, and resulted in average cumulative monthly reductions of 9 MWh per school with a hostel and 3 MWh per school without a hostel to October. The schools' bills were reduced between ZAR 11,000 and ZAR 50,000 over the April, May and June periods. One of the schools showed a sudden increase right after the rst two months of lockdown, hence there was an increase in bills in June 10 by ZAR 4,000. Some schools had increases in their electricity bills before the lockdown started. These schools show reductions in electricity costs when the lockdown started, as expected. Total billing reductions over the whole year ranges from ZAR 25,000 - 185,000. Because of the variance in the energy usage between schools, we also compared the e ect of all the schools by normalising the energy usage of each school according to the maximum-energy usage of the school over the entire 15 period (i.e. 2018/2019 and 2019/2020). These comparative results are shown in Figure 2a with the lockdown levels and with the shaded areas indicating the periods of school closure in 2019 (in grey) and 2020 (in red). The solid line constitutes the usage of the median school, with the shaded areas denoting the schools with the maximum and minimum normalised usage. The gure shows the high level of similarity between the schools from November to March, before the move to lockdown Level 5 on 26 March 2020. From the last week in March, a sharp reduction 20 is observed as schools were forced to shut their doors. This trend holds for all ve schools. In June, as sta and 4 /uni00000031/uni00000052/uni00000059 /uni00000027/uni00000048/uni00000046 /uni0000002d/uni00000044/uni00000051 /uni00000029/uni00000048/uni00000045 /uni00000030/uni00000044/uni00000055 /uni00000024/uni00000053/uni00000055 /uni00000030/uni00000044/uni0000005c /uni0000002d/uni00000058/uni00000051 /uni0000002d/uni00000058/uni0000004f /uni00000024/uni00000058/uni0000004a /uni00000036/uni00000048/uni00000053 /uni00000032/uni00000046/uni00000057 /uni00000031/uni00000052/uni00000059 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 /uni00000015/uni00000013/uni00000014/uni0000001c/uni00000012/uni00000015/uni00000013/uni00000015/uni00000013 /uni0000002b/uni00000052/uni0000004f/uni0000004c/uni00000047/uni00000044/uni0000005c/uni00000003/uni00000015/uni00000013/uni00000014/uni0000001c /uni0000002b/uni00000052/uni0000004f/uni0000004c/uni00000047/uni00000044/uni0000005c/uni00000003/uni00000015/uni00000013/uni00000015/uni00000013(a) Normalised-energy usage between 2018/2019 and 2019/2020 (rolling average of energy over 28 days) /uni00000031/uni00000052/uni00000059 /uni00000027/uni00000048/uni00000046 /uni0000002d/uni00000044/uni00000051 /uni00000015/uni00000013/uni00000014/uni0000001c/uni00000029/uni00000048/uni00000045 /uni00000030/uni00000044/uni00000055 /uni00000024/uni00000053/uni00000055 /uni00000030/uni00000044/uni0000005c /uni0000002d/uni00000058/uni00000051 /uni0000002d/uni00000058/uni0000004f /uni00000024/uni00000058/uni0000004a /uni00000036/uni00000048/uni00000053 /uni00000032/uni00000046/uni00000057 /uni00000003/uni00000010/uni00000017/uni00000013/uni00000008/uni00000010/uni00000015/uni00000013/uni00000008/uni00000013/uni00000008/uni00000015/uni00000013/uni00000008/uni00000017/uni00000013/uni00000008/uni0000003a/uni00000048/uni00000048/uni0000004e/uni0000004f/uni0000005c/uni00000003/uni00000046/uni0000004b/uni00000044/uni00000051/uni0000004a/uni00000048/uni00000003/uni00000049/uni00000055/uni00000052/uni00000050/uni00000003/uni00000053/uni00000055/uni00000048/uni00000059/uni0000004c/uni00000052/uni00000058/uni00000056/uni00000003/uni0000005c/uni00000048/uni00000044/uni00000055/uni00000003/uni0000000b/uni00000051/uni00000052/uni00000055/uni00000050/uni00000044/uni0000004f/uni0000004c/uni00000056/uni00000048/uni00000047/uni0000000c/uni0000002f/uni00000048/uni00000059/uni00000048/uni0000004f/uni00000003/uni00000013 /uni0000002f/uni00000048/uni00000059/uni00000048/uni0000004f/uni00000003/uni00000018/uni0000002f/uni00000048/uni00000059/uni00000048/uni0000004f/uni00000003/uni00000017/uni0000002f/uni00000048/uni00000059/uni00000048/uni0000004f/uni00000003/uni00000016/uni0000002f/uni00000048/uni00000059/uni00000048/uni0000004f/uni00000003/uni00000015/uni0000002f/uni00000048/uni00000059/uni00000048/uni0000004f/uni00000003/uni00000014 /uni00000030/uni00000048/uni00000047/uni0000004c/uni00000044/uni00000051/uni00000003/uni00000056/uni00000046/uni0000004b/uni00000052/uni00000052/uni0000004f /uni0000002b/uni00000052/uni0000004f/uni0000004c/uni00000047/uni00000044/uni0000005c/uni00000003/uni00000015/uni00000013/uni00000014/uni0000001c /uni0000002b/uni00000052/uni0000004f/uni0000004c/uni00000047/uni00000044/uni0000005c/uni00000003/uni00000015/uni00000013/uni00000015/uni00000013 (b) Normalised-energy di erences between 2018/2019 and 2019/2020 (aggregated weekly). Figure 2: Comparison of energy usage over the two-year period. children returned to a partially-opened school usage increases, but since the schools are only partially open, only to levels substantially less than those seen in the previous year during the July holidays. This is accentuated by the sharp diversion between the years' pro les in the second half of July, when the schools opened from holidays in 2019. The same trend is seen in the overlapping range of the last week of September, when the schools were still partially open in 2020, but a holiday was in e ect in 2019. Thereafter, the plots diverge again. 5 It is clear that the energy usage during the lockdowns in 2020 was equal to or lower than the holiday periods of 2019. An interesting conclusion is that more energy-using devices could probably have been turned o during the holidays of 2019. Another observation is that even during the Level 5 lockdowns, a substantial base-load energy was still observed at each of the schools, possibly indicating further potential savings. The minimum load (energy per hour) detected at any school was 6 kWh over the second set of 12 months. 10 The di erence in normalised-energy usage was also calculated for each week of the period under investigation. These di erences are shown in Figure 2b for the median, minimum, and maximum using schools. The gure clearly shows the two peaks of increase in the di erences over the lockdown periods, and a zero-crossing delta over the period where schools were closed over 2019 for a short holiday and partially open during 2020 in the last week of June. 15 Table 4 lists the reduction in energy usage per calendar day over speci c-time periods, which is calculated by comparing the total usage per day for the 2018/2019 period with the 2019/2020 period. Level 0, meaning not 5 in lockdown, is included to show the energy usages in the period before the lockdown transition to Level 5. The duration of the levels are shown in parentheses. Di erence in schools' energy usage [kWh/day] School 1 School 2 School 3 School 4 School 5 Level 0 (69 days) 22.14 33.80 -30.93 55.14 -21.75 Level 5 (34 days) -184.91 -96.18 -477.82 -127.74 -78.15 Level 4 (31 days) -184.35 -90.13 -635.16 -232.81 -99.52 Level 3 (77 days) -117.47 -62.03 -400.84 -204.05 -68.26 Level 2 (34 days) -134.91 -196.76 -390.47 -242.03 -52.82 Level 1 (29 days) -52.28 -151.34 -196.52 -94.97 -3.48 Table 4: Energy reduction in kWh (average change in kWh/day) The expectation is that school would use more energy when the learners are present, hence the most electricity usage would be reduced at Level 5 (assuming that more learners are at home and schools were closed) and then lesser reductions would be present towards the less restrictive levels of lockdown i.e. level 1. 5 We used the results in Table 4, the complete school closure during the Level 5 lockdown to calculate an estimated energy usage per student. For the ve schools in the order from School 1 to School 5, this results in a reduction during Level 5 per student of 9 :2 kWh =month, 3 :6 kWh =month, 19 :9 kWh =month, 7 :0 kWh =month, 2 :0 kWh =month 4. Conclusion The devastating impact of COVID-19 will be felt for years, if not decades, especially in developing countries 10 and poor regions. Among other, it is also expected to have a disastrous impact on schooling in the region due to absences and dropouts. In this paper, we assessed the ip side of the absence coin, by empirically analysing energy savings achieved in schools in our sample over the lockdown period. These results quantify usage due to occupancy, and also the baseline despite zero occupancy. We observed average energy reductions of 33% for schools with hostels, and 25% for schools that do not have 15 hostels. These are the equivalent of reductions of up to 9 MWh per month per school, and monthly bills by as much as ZAR 50,000. To allow a like-for-like comparison, we normalised the energy usage at each school to a peak observed value, and plotted the schools' normalised usage year-on-year. The results show the substantial reduction ranging between 30% and 40% during the hard lockdown. 20 The results further showed that savings per learner ranged between 2 to 20 kWh =month. It was also found that energy usage during hard lockdowns or even holidays in 2019 still showed substantial base-load which indicates a need for future explorations of energy saving interventions and technologies for schools in South Africa.