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shows how it was measured.

Real sites. Each case starts with a problem, then how we found the cause, chose a fix and what changed.

Methods publicBad data includedEstimates labeled
7 full cases · 2 in progress
HVAC savingLatest · 24-hour store

Convenience store HVAC test: about 7% energy saving at similar outdoor temperatures

A 24-hour convenience store fitted passive panels to 2 cassette units. 14 days before and after, grouped by outdoor temperature, plus two similar days compared hour by hour.

Site
Chain convenience store (anonymized)
Scale
2 ceiling cassette AC units, 6 kW rated in total
Period
2025/6/18 – 7/16 (14 days before and after)
9 / 9temp bins lower
6.95%two similar days
17.05%14-day total (upper bound)

EstimatedAnnualized at 7–17%: about 919–2,231 kWh saved, NT$3,500–8,500 in power costs, 0.44–1.06 t of carbon

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Fig. 01 — By outdoor temperatureAverage energy
BeforeAfter
12345Outdoor 25°C before 0.72 kWhOutdoor 25°C after 0.55 kWh-24%25°Outdoor 26°C before 1.65 kWhOutdoor 26°C after 1.25 kWh-24%26°Outdoor 27°C before 1.04 kWhOutdoor 27°C after 0.61 kWh-41%27°Outdoor 28°C before 2.37 kWhOutdoor 28°C after 1.9 kWh-20%28°Outdoor 29°C before 2.88 kWhOutdoor 29°C after 2.66 kWh-8%29°Outdoor 30°C before 2.5 kWhOutdoor 30°C after 2.12 kWh-15%30°Outdoor 31°C before 3.19 kWhOutdoor 31°C after 2.17 kWh-32%31°Outdoor 32°C before 3.95 kWhOutdoor 32°C after 2.78 kWh-30%32°Outdoor 33°C before 5.24 kWhOutdoor 33°C after 4.73 kWh-10%33°kWh
Two similar days44.58→41.48kWh−6.95%

All 9 bins (25–33°C) dropped. Hourly, 19:00 and 20:00 rose — shown as is.

HVAC savingCross-season test

No new AC, 12.2% summer saving: a retail store test

A clothing store added passive panels to its AC. We compared energy use before and after across spring and summer, matching time of day, outdoor temperature and units running.

Site
An international chain clothing store in northern Taiwan
Scale
12 outdoor units, 3 of them the main test units
Period
2026/2/26 – 8/5 (spring and summer)
7.8%Spring saving
12.2%Summer saving
13.5%All 12 units

EstimateAt the summer rate: ~21,219 kWh, NT$102k, ~10 t CO₂ a year

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Fig. 01 — 12 outdoor units in summerAverage hourly energy use
BeforeAfter
Main test units1234Unit A before 1.28 kWh/hUnit A after 1.16 kWh/hAUnit B before 0.78 kWh/hUnit B after 0.69 kWh/hBUnit C before 1.02 kWh/hUnit C after 0.85 kWh/hCUnit D before 0.28 kWh/hUnit D after 0.35 kWh/hD+0.07Unit E before 1.3 kWh/hUnit E after 1.17 kWh/hEUnit F before 4.34 kWh/hUnit F after 3.58 kWh/hFUnit G before 1.09 kWh/hUnit G after 1.03 kWh/hGUnit H before 1.2 kWh/hUnit H after 0.95 kWh/hHUnit I before 0.4 kWh/hUnit I after 0.36 kWh/hIUnit J before 2.06 kWh/hUnit J after 1.76 kWh/hJUnit K before 0.73 kWh/hUnit K after 0.68 kWh/hKUnit L before 1.41 kWh/hUnit L after 1.15 kWh/hLkWh/h
Overall15.87→13.74kWh/h−13.5%

11 of 12 units dropped; Unit D rose 0.07 kWh/h, shown as is. Not condition-matched; trend only.

More cases

More full case write-ups coming
08

Chip packing: 36 → 6 staff on three shifts

Inner-box packer × logistics line (anonymized)
36 → 6packing staff
↓ 83%staffing, best case
40–50%avg. fewer staff
Write-up coming
09

B2B digital marketing for export growth

Targeted ads × lead generation
↑ 3×leads
↑ 50%sales conversion
New marketentered
Write-up coming

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