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https://exlibrisgroup.com

Sustainability

· 6 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.
SCORE
63
GRADE
D
FIX
2
REVIEW
1
PASS
3
INFO
0
Device:
Mobile Desktop
Checks
6
3 PASS 1 REVIEW 2 FIX
F
CO2 Per Page Load
Action
8.00g CO2 per view
FIX
8.00g CO2 per view
Critical::
8.00g CO2 per page view
This page transfers 33.8 MB, producing an estimated 8.00g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.20g, network 1.65g, end-user device 6.14g.
Got: 8.00g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 959.9 kg CO2/year
With 10,000 page views per month, this page would generate approximately 959.9 kg of CO2 annually — equivalent to charging 119984 smartphones.
Info::
Green hosting reduces data center emissions

8.00g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 5% of websites

Sustainable Web Design model v4 · Page size: 33.8 MB

Your site
8.00g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.20g
Network
1.65g
End-user device
6.14g
At 10,000 monthly views: Monthly: 80.0 kg · Annual: 959.9 kg · ≈ 119984 smartphone charges
F
Carbon Budget
Action
95th percentile
FIX
95th percentile
Warning::
8.00g CO2 — above the median website (0.60g)
Heavier than an estimated 5% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 95th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

8.00g

95th percentile

Cleaner than 5% of websites

✗ Above the median website

vs Median 1233% more
vs Target 1500% more
C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A
Green Hosting
Green (cdn)
PASS
Green (cdn)
Info::
Fastly CDN uses renewable energy
Since most traffic is served through the CDN, the majority of data transfer energy is renewable.
Info::
Fastly: 100% renewable energy for edge network
Info::
Green hosting status based on known provider commitments
Green hosting detection uses a curated database of provider renewable energy commitments. This is not a real-time verification. For authoritative checks, visit thegreenwebfoundation.org.
Green Hosting✓ Green Hosted
Hosting Pantheon✗CDN Fastly✓

Fastly: 100% renewable energy for edge network

Based on known provider commitments. Verify at thegreenwebfoundation.org

A+
Repeat Visit Weight
100% cached
PASS
100% cached
Info::
100% reduction on repeat visits
Returning visitors download only 99 KB (vs 34606 KB first visit). 440 of 442 resources are served from browser cache, saving 7.98g CO2 per repeat visit.
Info::
Repeat visit: 0.02g CO2 (first visit: 8.00g)
First visit
34606 KB
Repeat visit
99 KB

100% reduction on repeat visits

Saving 7.98g CO2 per returning visitor

440 resources served from cache · 2 resources re-downloaded

A+
Transfer Efficiency
98% efficient
PASS
98% efficient
Info::
Transfer efficiency: 98%
Only 615 KB of potential savings identified. Your page is well-optimized for size.
98% efficient

Total waste: 615 KB (2% of page weight)

Unused JS 615 KB

0.14g unnecessary CO2 per visit

Actual transfer 34606 KB
Theoretical minimum 33991 KB
Potential savings 615 KB (0.14g CO2)

See Deep Analysis sections above for specific optimizations.

All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.

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