Telemedicine and the environment: life cycle environmental emissions from in-person and virtual clinic visits

Healthcare is a major contributor to national greenhouse gas (GHG) emissions, prompting efforts to quantify and reduce the sector’s environmental footprint. Telehealth has rapidly expanded, especially following COVID-19-related policy changes enabling reimbursement parity, and is posited to reduce emissions largely by eliminating patient travel. Prior evaluations often focus narrowly on travel and/or single specialties. This study aims to quantify, via life cycle assessment (LCA), the GHG emissions associated with in-person versus telemedicine (phone and video) clinic visits across an academic health system (Stanford Health Care), assessing whether telemedicine can increase access while decreasing system-level carbon emissions.

Existing work indicates telehealth can reduce patient miles traveled and associated emissions, with added benefits such as improved access, lower opportunity costs, and high patient satisfaction. Reported GHG savings per telehealth visit vary widely due to differing methods and system boundaries. Transportation is commonly the dominant emissions source for in-person care, though other contributors include PPE, supplies, and facility energy. Some contexts (e.g., certain hospitals) find electricity to be a large contributor, highlighting heterogeneity across settings and specialties. Policy shifts during the pandemic expanded telehealth reimbursement, but ongoing debates (e.g., payment parity for phone-only visits) and differences in local energy mixes and transport infrastructure can affect realized environmental benefits.

Design: Environmental Life Cycle Assessment (LCA) per ISO 14040 with four phases: goal and scope, inventory, impact assessment, and interpretation. Functional unit: one clinic visit (in-person or virtual). Setting: Stanford Health Care (SHC), an academic health system in Palo Alto, CA, with 65 clinics, using retrospective data from 2019–2021. Scope and system boundaries: For in-person visits, included patient round-trip transportation (mode based on distance: >402 km one way assumed air; ≤402 km assumed passenger car), exam room energy (HVAC and lighting) during visit duration using SHC-measured energy intensity applied to a 10’x10’ (9.3 m²) room, and typical supplies and waste (assumed minimal list: surgical mask at 1 per 10 visits, exam table paper cover, one pump of hand sanitizer, one sanitizing wipe). Supplies were modeled with manufacture in China, ~3000 km ocean shipping, 40 km trucking distribution to clinic, and 40 km trucking to landfill for disposal. For virtual visits, included electricity to power patient’s phone (for audio) or to run video conferencing, and clinician’s desktop computer in clinic. Excluded: HVAC energy for provider/patient spaces during virtual visits due to allocation challenges; staff commuting for either visit type; patient-side energy beyond device use; potential conversions/failures of virtual to in-person visits (assumed all virtual visits were appropriate). Data sources: SHC Digital Health Care Integration team provided counts and durations of in-person, phone, and video visits by department (2019–2021). SHC Engineering provided clinic energy consumption (electricity, gas, steam, chilled water) and floor area to derive per-minute, per-square-foot energy intensity. Inventory and modeling: SimaPro 9.3 with Ecoinvent v3.8 (allocation, cut-off by classification). Impact assessment: US EPA TRACI 2.1 (US 2008). Primary outcome: GHG emissions (kg CO2e and metric tons CO2e) per visit and in aggregate by year and mode; other impact categories reported in Supplementary Information. Avoided emissions estimation: Modeled 2021 virtual visits as if they occurred in person (adding patient transportation, in-person supply chain and waste, and room energy for the same visit duration) and compared to modeled virtual visit emissions. Sensitivity analyses (2021): - Travel mode: all patients traveling by car (versus baseline distance-based air/car assumption). - Facility energy variability: minimum/maximum clinic energy intensity and exam room sizes. - Electricity grid mix: baseline WECC; solar in WECC; US average grid. - Supplies: a maximum, conservative supply list (e.g., gloves, gowns for provider and patient, mask, wipe, table cover, sanitizer) to test upper-bound effects. - Transportation modes: exploratory scenarios across multiple transit modes (e.g., bicycles, bus, various car fuel types) using Ecoinvent processes.

- Visit volume and emissions trends: SHC visits increased 13% from 1,733,020 (2019) to 1,961,768 (2021), yet modeled GHGs from clinic visits decreased 36% from ~40,600 to ~25,900 metric tons CO2e (baseline assumptions). - Per-visit emissions (2021): In-person average ~20 kg CO2e/visit; phone ~0.02 kg CO2e/visit; video ~0.04 kg CO2e/visit. Virtual visits emit less than 1% of in-person visit emissions. - Virtual visit volumes (2021): 59,635 phone visits; 612,700 video visits. - Emissions sources for in-person care: Patient transportation dominates. In 2019, emissions were ~49% air travel and 51% car; in 2021, ~44% from an estimated 93.9 million km airline travel and ~55% from 42.9 million km car travel. - Virtual visit device energy (2021): ~29,000 kg CO2e, equivalent to ~3,252 gallons of gasoline burned or annual energy use of ~3.6 US homes. - Avoided emissions due to telehealth (2021): Nearly 17,000 metric tons CO2e avoided relative to treating those patients in person. - Departmental adoption (2021, % visits virtual): Psychiatry 88%; Medical specialties 73%; Pain management 68%; GI surgery 63%; Cancer 47%. Low adoption: Ophthalmology 1%; Plastic surgery 7%; Orthopedics 11%; Otolaryngology 18%. - Emissions by department: Lowest in-person per-visit emissions in primary care and pediatrics (7.33 kg CO2e/visit), highest in orthopedics (63.8 kg CO2e/visit). Virtual visits ranged 0.02–0.08 kg CO2e/visit by department. - Sensitivity analyses (2021): • If all patients traveled by car, in-person visit emissions increased by 77% (from ~25,700 to ~45,400 metric tons CO2e). • For virtual visits, solar electricity reduced emissions by ~70%, while the US average grid increased telehealth emissions by ~20% relative to WECC baseline. • A maximum supply list for in-person visits increased total 2021 in-person GHGs by ~1.1% (~277,000 kg CO2e). • Variations in clinic energy intensity and exam room size had minor effects compared to transportation assumptions.

Telemedicine substantially reduced SHC’s clinic visit-related GHG emissions despite growth in total visit volume. Transportation is the dominant emissions driver for in-person visits, so shifting suitable encounters to virtual formats yields large reductions. Virtual visits at SHC produced under 1% of the GHGs of in-person visits, underscoring their environmental advantage. Adoption and benefits vary by specialty, reflecting differences in reliance on physical exams, procedures, and patient travel distances. The study extends prior literature by including supplies, facility energy, and device electricity, not just travel. Implementation considerations include patient satisfaction, clinical effectiveness, cost, and equitable access to technology. Policy environments (e.g., reimbursement parity) influence uptake and the realized environmental benefits. Broader decarbonization of electricity grids would further reduce telemedicine’s footprint, whereas growing broadband and higher-quality video may increase device energy intensity if grids remain carbon intensive. Telehealth should be deployed where clinically appropriate, with attention to avoiding duplicative visits that could negate environmental and operational gains.

Telemedicine can meaningfully reduce health system GHG emissions, primarily by avoiding patient transportation for appropriate visits. At SHC, telehealth enabled a 36% reduction in clinic visit-related emissions from 2019 to 2021 amid a 13% increase in visits and avoided nearly 17,000 metric tons CO2e in 2021. Departments with higher suitability for virtual care achieved greater reductions. While telemedicine cannot replace all in-person encounters, integrating robust triage, tracking, and specialty-specific guidelines can maximize successful virtual visits and minimize duplicative care. Future research should quantify virtual-to-in-person conversion rates, develop specialty- and diagnosis-specific appropriateness criteria, refine allocation of HVAC and shared space energy in virtual visits, and explore impacts of different transport modes and regional energy mixes to inform policy and operational decisions.

- HVAC and broader space conditioning for providers’ and patients’ locations during virtual visits were excluded due to allocation challenges. - Assumed all virtual visits were appropriate (no conversion to in-person), potentially overestimating net savings if duplicative visits occur. - Did not include staff commuting for either visit type. - Patient travel distances and modes were not directly measured; distances were estimated from ZIP codes and modes inferred with a 402 km cutoff for air travel. - Supply chains were simplified (e.g., manufacturing in China, average shipping distances), which may differ by product and clinic. - Energy intensity applied uniformly on a per-area, per-minute basis may not fully capture operational schedules or variability across clinics. - Results are context-dependent (regional transport patterns, clinic energy profiles, grid mixes) and may vary in regions with robust public transit or different energy mixes.