# Load Shedding Downtime Loss Log Worksheet > Source: https://netray.co/tools/load-shedding-downtime-loss-log-worksheet > Publisher: Netray (netray.co), AI and integration engineering for ERP and manufacturing systems. > Section: Free Tools ## Short answer An editable outage log that turns grid downtime and generator hours into lost units, lost contribution and diesel cost per shift. ## Category manufacturing ## Region Africa ## Industry Manufacturing ## Audience - Plant manager - Production manager - Maintenance manager ## Tool **Kind:** worksheet **Mode:** editable **Currency:** R **Columns:** #### Date **Key:** date **Type:** date #### Line or cell **Key:** line **Type:** text #### Outage type **Key:** stage **Type:** select **Options:** - Load shedding - Grid fault - Brownout - Generator fault #### Hours stopped **Key:** stopped **Type:** number **Unit:** h #### Hours on generator **Key:** gen **Type:** number **Unit:** h #### Units per hour **Key:** rate **Type:** number #### Contribution per unit **Key:** contrib **Type:** number **Format:** currency #### Diesel per hour (L) **Key:** diesel **Type:** number #### Lost units **Key:** lost_units **Type:** number **Expr:** stopped * rate **Format:** integer #### Lost contribution **Key:** lost_margin **Type:** number **Expr:** stopped * rate * contrib **Format:** currency #### Diesel used (L) **Key:** diesel_l **Type:** number **Expr:** gen * diesel **Format:** number **Rows:** **Date:** 2026-10-05 **Line:** Press line 1 **Stage:** Load shedding **Stopped:** 2.5 **Gen:** 0 **Rate:** 120 **Contrib:** 38 **Diesel:** 0 **Date:** 2026-10-05 **Line:** Packing **Stage:** Load shedding **Stopped:** 0.5 **Gen:** 2 **Rate:** 300 **Contrib:** 6 **Diesel:** 18 **Date:** 2026-10-08 **Line:** Press line 1 **Stage:** Grid fault **Stopped:** 4 **Gen:** 0 **Rate:** 120 **Contrib:** 38 **Diesel:** 0 **Date:** 2026-10-12 **Line:** CNC cell **Stage:** Generator fault **Stopped:** 3 **Gen:** 0 **Rate:** 14 **Contrib:** 410 **Diesel:** 0 **Date:** 2026-10-15 **Line:** Packing **Stage:** Brownout **Stopped:** 1 **Gen:** 3 **Rate:** 300 **Contrib:** 6 **Diesel:** 18 **Totals:** #### Total hours stopped **Key:** stopped **Agg:** sum **Format:** number #### Total lost units **Key:** lost_units **Agg:** sum **Format:** integer #### Total lost contribution **Key:** lost_margin **Agg:** sum **Format:** currency #### Total diesel (litres) **Key:** diesel_l **Agg:** sum **Format:** number **Summary:** #### Lost contribution per stopped hour **Key:** margin_h **Expr:** sum_lost_margin / sum_stopped **Format:** currency **Primary:** true #### Outage events logged **Key:** events **Expr:** count **Format:** integer **Notes:** Diesel cost is shown in litres so you can multiply by your current price. Use the contribution per unit (price less variable cost), not the full selling price, so the loss is not overstated. ## Content **Intro:** Frequent power interruptions are a daily reality for manufacturers in several African countries, but few plants know what they cost per line. This log records each event and converts it into lost units, lost contribution and generator diesel. **Sections:** #### How to use the log **Body:** Add a row for each outage or generator event. Enter the line, the hours it stopped, the hours it ran on generator, its normal output per hour, the contribution per unit and the generator's diesel burn per hour. The sheet calculates lost units, lost contribution and litres used. Review weekly and export to Excel for management reporting. **Bullets:** - Use actual stop and start times from the shift report - Record generator hours separately from stopped hours - Use contribution margin, not selling price - Tag the cause so you can compare grid and equipment faults #### Method **Body:** Lost units are hours stopped times the normal rate. Lost contribution multiplies that by the contribution per unit, which is selling price less variable cost. Diesel used is generator hours times consumption per hour. The summary divides total lost contribution by total stopped hours, giving a cost per stopped hour that you can compare against the cost of running a generator or installing solar and storage. #### Reading the result **Body:** In the sample data, the press line and the CNC cell account for most of the lost contribution even though packing is stopped more often, because contribution per hour differs. Prioritise backup power on the lines with the highest contribution per hour, not simply those with the most interruptions. #### Common mistakes **Body:** Plants often count partial hours loosely, ignore the restart and warm up time after an outage, or value lost output at full price. Where scrap or rework follows an abrupt stop, record it separately in your quality system. In an ERP, outage events can be posted as downtime reasons on production orders for later analysis. **Cta:** If you want outage and downtime reasons captured from the shop floor into your ERP automatically, Netray can discuss how to wire that in. **Faq:** #### How is lost contribution calculated? **Answer:** Hours stopped times output per hour times contribution per unit. Contribution is price minus variable cost, so fixed overhead is excluded and the loss is not overstated. #### Does it include diesel cost in money? **Answer:** It shows litres, so you can apply your current diesel price. This avoids baking an out of date price into the log. #### Can I use it for non-African plants? **Answer:** Yes. Any plant that suffers power interruptions can use the same method. The title refers to load shedding because that is how many African plants describe the problem. #### Can I share it with my team? **Answer:** Export to Excel or CSV and share the file. The page itself does not store your data. ## Search terms load shedding downtime log, power outage log manufacturing, load shedding production loss excel, generator running hours log, downtime log template excel, cost of power outages factory --- Talk to an engineer: https://netray.co/contact?intent=erp_ai | Machine catalog: https://netray.co/agent/catalog.json