Sustainability of Video Streaming: OTT vs OTA

As viewers increasingly shift from traditional over-the-air (OTA) broadcast TV to over-the-top (OTT) internet streaming, questions arise about which delivery method is kinder to the planet. Does streaming video on demand carry a bigger carbon footprint than watching free-to-air television? This in-depth lesson examines how OTA and OTT systems work, their energy use and carbon emissions, and what the latest research (especially a UK Ofcom study) tells us about their sustainability. We’ll compare their efficiency, discuss broader environmental factors, highlight industry initiatives, and explore innovations that could make video distribution greener for the future.

What Are OTA and OTT Video Delivery?

Over-the-Air (OTA) Broadcast refers to traditional television delivery through terrestrial transmitters, broadcasting signals through the air that anyone with an antenna can receive. In the UK, OTA primarily means Digital Terrestrial Television (DTT) – for example, the Freeview service that delivers BBC, ITV, Channel 4, and other channels via a network of transmitters. These broadcast towers send one-way radiofrequency signals that carry scheduled TV channels to the public. A single high-power transmitter can reach millions: the UK’s transmitter network (managed largely by Arqiva) includes over 1,100 sites and covers around 95% of the population​. Viewers simply tune their TV (or set-top box) to the channel; the content is delivered one-to-many, meaning one broadcast stream is shared simultaneously by all watchers. Besides DTT, OTA can include traditional radio, and one could loosely include satellite and analog broadcasts under OTA, though here we focus on terrestrial TV transmission.

Over-the-Top (OTT) Streaming delivers video via internet Protocol (IP) networks – essentially through the public internet “on top” of existing broadband infrastructure rather than dedicated broadcast spectrum. OTT services include platforms like Netflix, Amazon Prime Video, Disney+, and catch-up or live streaming apps such as BBC iPlayer, ITVX, All4, and YouTube. Content is delivered on-demand or via live streams to each user individually. When you hit “play” on an OTT app, the video data is sent from data centers or content servers across the internet to your device (smart TV, smartphone, tablet, laptop, etc.). This is a unicast (one-to-one) delivery – each stream is a unique connection, so 100,000 people watching the same show online means 100,000 separate streams traversing the network (albeit often served via cached copies on regional Content Delivery Network nodes). OTT relies on the telecom networks (fixed broadband or mobile data) to carry the content, and thus requires a robust two-way network connection for each viewer.

Usage in the UK: Both OTA and OTT are widely used and increasingly complementary. Virtually all UK households have access to OTA broadcast TV (DTT/freeview or cable/satellite), and traditional live TV still accounts for a large share of viewing. However, OTT streaming has grown rapidly – Ofcom’s 2022 data shows that on average 41% of viewing time was spent on non-broadcast content (streaming, YouTube, etc.), with 59% still on broadcast content​. Public service broadcasters (BBC, ITV, Channel 4) now offer extensive OTT platforms alongside their OTA channels, though in 2021 only about 10% of those broadcasters’ viewing was via their OTT apps (90% remained live/broadcast). Meanwhile, pure streaming services (Netflix, etc.) have become mainstream. Notably, most OTT streaming in the UK is done on television screens as well – around 75% of OTT viewing hours in 2021 were on a TV (smart TV or via streaming devices), with the rest on smaller devices like phones, tablets, or computers​. In summary, OTA and OTT currently coexist: broadcast TV excels at reaching mass audiences reliably (e.g. live sports, news), while OTT provides on-demand convenience and niche content. Now, let’s compare their environmental footprints.

Carbon Footprint & Energy Efficiency: OTA vs OTT

Delivering video content – whether by broadcast towers or internet servers – consumes energy and thus has a carbon footprint (unless all that energy is from renewable sources). A recent study commissioned by Ofcom (UK’s telecom regulator) provides one of the best snapshots of how energy-hungry OTA vs OTT are per hour of TV watched, under UK conditions. The findings might surprise you:

• Energy per Viewing Hour: Watching via OTA (DTT) is significantly more energy-efficient on a per-hour per-viewer basis than OTT streaming. According to Ofcom’s 2021 analysis, one hour of television via DTT uses roughly 9–11 Wh (Watt-hours) of electrical energy per viewer, whereas one hour via OTT streaming uses about 54 Wh​. In other words, streaming can consume around five times more energy for the same hour of video content delivery. To put that in everyday terms, watching TV for an hour (either way) uses a relatively small amount of energy – roughly equivalent to boiling a kettle for 3–4 cups of tea​  – but OTT’s portion of that energy is the larger share.
  
• Where Is the Energy Consumed?: Interestingly, the vast majority of energy in both cases is used by the devices in our homes, not by the broadcast transmitters or internet infrastructure. The Ofcom study found about 90–96% of the energy consumption comes from in-home equipment (TV displays, streaming boxes, Wi-Fi routers, etc.), with only a single-digit percentage attributed to the network distribution outside the home​. For OTA, nearly 96% of the energy for an hour of viewing is due to the television (and any set-top box/antenna amplifier), whereas the actual broadcast network transmission accounts for only ~4%. For OTT, about 90% is from the user’s device and home networking (Wi-Fi/router), with ~10% coming from the data centers, content delivery networks (CDNs), and telecom network that carry the stream​. This is because modern TV sets and streaming devices draw tens of watts of power, while the energy used in transmitting or routing the data for that one hour (when averaged per viewer) is relatively small.
  
• Network Energy and Scalability: Although the network portion is small in percentage terms, OTT’s distribution is more energy-intensive than broadcast’s. Outside the home, delivering an hour of OTT video consumes about six times more network energy than delivering an hour via DTT broadcast, given today’s usage volumes​. Each OTT stream puts load on servers and data networks (access networks, core internet, routers), which consume electricity to move data. By contrast, an OTA broadcast sends out one signal that uses a fixed amount of transmitter power whether one person or a million people tune in – so per viewer, the energy cost of the distribution network is minuscule. This highlights a key scalability difference: OTA is one-to-many with economies of scale (the more people watch, the lower the energy per viewer), whereas OTT is one-to-one, meaning its total energy usage scales roughly in proportion to number of streams (more viewers = more cumulative server and network work). If viewership grows, OTT requires expanding network capacity and energy, while OTA can add extra viewers with virtually no extra transmission energy​. As one industry article put it, a broadcast network’s energy use is largely fixed and “a change in viewership levels will not increase or decrease the deployed capacity”, whereas rising OTT consumption is a driver of increased internet traffic and infrastructure​.
  
• Fixed Energy vs. On-Demand Efficiency: An OTA transmitter operates continuously at a set power level broadcasting content regardless of how many are watching or whether the TV is on. This means if an OTA channel has very low audience, the energy per actual viewer can become high (since the transmitter is still on). OTT, on the other hand, only uses significant transmission energy when a stream is requested – no stream, no data sent. This makes OTT potentially more efficient for very low-viewership or niche content, since you wouldn’t power a nationwide transmitter for just a handful of viewers. However, for popular content watched by many people at the same time, broadcast is far more efficient because it avoids duplicating streams. In practice, broadcasters and streamers are aware of this trade-off. For example, a major live event (like the World Cup final) can be delivered to millions via a single OTA broadcast, whereas OTT would require millions of duplicate streams – a much heavier load on servers and networks. Conversely, a niche interest show might be better delivered on-demand to those few who want it, rather than occupying a full-time broadcast channel. The Ofcom report uses an “attributional” method to compare energy per viewing-hour under current average conditions​, and cautions that these figures are a snapshot for today’s mix of viewers and technology, not a prediction of the future​. If many viewers migrate from broadcast to OTT or vice versa, the relative efficiency could shift (for example, an under-utilized broadcast multiplex is wasteful, while a well-optimized streaming network at scale could become more efficient over time).
  
• Energy Intensity and Improvements: It’s worth noting that absolute energy use for TV viewing is low compared to many other activities. Both distribution methods have seen improvements in efficiency. Telecom networks have continually improved their energy per bit – carrying more data traffic over the same energy​  – and broadcasters have upgraded transmission equipment for better power efficiency. Still, the current data indicates OTT is generally more energy intensive than DTT broadcast for delivering one viewer-hour of TV​. In 2021, OTT in the UK was roughly 48% more energy per device-hour than DTT when averaged across all devices and viewers​. The gap had narrowed from prior years as streaming technology and viewing patterns evolve, but OTT remains the less efficient delivery in pure energy terms for now.
  

To illustrate the comparison, consider an example: If you watch a one-hour TV episode on BBC1 via Freeview (DTT), the transmitter and your TV together might consume on the order of 50 Wh (0.05 kWh) in total, whereas streaming a one-hour episode from iPlayer could consume around 50–60 Wh in your TV and streaming box plus another ~5–6 Wh in the network infrastructure, totaling ~55 Wh. The majority of that energy in both cases is your TV – which is roughly the same in either scenario if you’re using the same device – but OTT incurs a higher overhead in the network. If you instead watched on a tablet or phone (lower power device), the device energy drops significantly, which might give streaming an edge in that circumstance (more on this next).

Finally, while energy use correlates with carbon emissions, the carbon footprint depends on how the electricity is generated. If the power comes from fossil fuels, those Wh translate to CO₂ emissions; if from renewables, the emissions are much lower. In the UK, grid electricity had an average emissions factor around 0.29 kg CO₂ per kWh in 2021​. Using that, 54 Wh of streaming equated to roughly 15–16 g CO₂ per viewer-hour, and 10 Wh of DTT to about 3 g CO₂. Both are quite small in carbon terms (a few grams is like a sip of petrol), and as grid electricity gets greener, the carbon difference shrinks. Indeed, many UK broadcast and broadband operators already use 100% renewable electricity for their operations – for example, Arqiva’s transmitter network was 99% powered by renewable energy in 2021, and BT’s broadband network and data centers use 100% renewable power​. This means the operational emissions from running these networks can be near-zero, turning the focus to energy consumption as a resource efficiency and cost issue, and to embodied carbon (manufacturing equipment) as the next challenge.

In Summary – Efficiency at a Glance:

To summarize the comparison of OTA vs OTT on key efficiency metrics, the table below highlights some differences:

Table: Comparison of OTA vs OTT in distribution and energy characteristics.

In short, digital broadcast (OTA) is inherently efficient for delivering the same content to large audiences, while OTT is flexible and personalized but incurs higher energy per viewer due to its unicast nature. Next, we’ll consider other sustainability factors beyond just the direct energy of streaming vs broadcasting.

Beyond Energy Use: Sustainability Implications

Looking at pure energy per hour is important, but the sustainability picture is broader. We must consider how user behavior, device choices, infrastructure demands, and content delivery models affect the environmental impact of video. Let’s explore some of these factors:

• User Behavior & Viewing Habits: How, when, and what we watch can influence energy usage. For example, binge-watching a series on OTT might mean hours of continuous streaming, potentially at high definition – increasing data transfer and keeping devices active longer. Conversely, traditional TV viewing may include leaving a TV on in the background or channel surfing, which also consumes energy. Auto-play features on streaming apps (queuing the next episode) can lead to longer viewing sessions (and thus more energy) than originally intended. On the other hand, streaming services often stop after a few episodes to ask “Are you still watching?”, which can save energy if the viewer has fallen asleep or left. Viewer count per device also matters: watching as a family on one TV is more energy-efficient (per person) than each family member streaming separately on their own device. In fact, the Ofcom study assumed an average of about 1.57 viewers per TV in the UK (since many households watch together, which is one reason why per-viewer energy for OTA looked so low. If streaming leads to more individualized viewing (everyone on personal screens), it could increase total energy use relative to group TV viewing.
  
• Device Energy Use: The type of device used to watch content is a major determinant of energy consumption. A modern large-screen LED TV might draw anywhere from 50W to 150W when on, depending on size and settings, and older plasma TVs even more. A streaming set-top box or console can add another 5–20W. Meanwhile, a smartphone or tablet might only use 1–5W when playing video, and a laptop perhaps 20-30W. This means watching on a small mobile device can use far less electricity than using a big TV. The Carnstone/Ofcom report explicitly notes a smartphone was estimated at ~1W for video streaming, versus 65.6W for a typical television (and ~100W for a high-end smart TV)​
  . Thus, if a chunk of OTT viewing shifts to mobile devices (as is common for younger viewers or certain content like short online videos), the device-side energy drops dramatically, improving OTT’s overall efficiency. In fact, from a device efficiency perspective, OTT can appear more efficient precisely because not all OTT content is watched on energy-hungry TVs​. By contrast, nearly all live OTA TV viewing involves a TV set. However, there is a flip side: many OTT users still favor the “10-foot experience” on a big screen for movies, sports, etc. (again, 75% of OTT hours in the UK are on TVs​), so the device energy advantage of mobile streaming is partially offset by the prevalence of TV-based streaming. Another consideration is gaming consoles – some people stream video via an Xbox or PlayStation, which can consume 100–200W (consoles are not optimized for video efficiency). Using a console to watch Netflix can use 10× more power than a dedicated streaming stick or smart TV app. Educating consumers to use more efficient streaming devices for video (or manufacturers improving console video power management) is an opportunity to reduce OTT energy use.
  
• Always-On Equipment & Idle Energy: A lot of the energy associated with our viewing setup isn’t even during active viewing. Idle or standby power draws can add up. In OTT, your home internet router and Wi-Fi access point are typically on 24/7, consuming a few watts continuously (which over a year can be 20–50 kWh). If you have a streaming device that doesn’t fully power down, it might sip power waiting for a command. Similarly, with OTA, if you use a PVR (personal video recorder) or set-top box, it might be running in standby to record scheduled programs or for quick start-up, drawing power all day. The Ofcom study pointed out that peripheral devices like Wi-Fi routers and set-top boxes “always on” can significantly contribute to energy consumption in the home​. From a sustainability standpoint, reducing idle power waste is important: e.g., next-gen routers and TVs with low-power standby modes, or using features like auto-shutdown of streaming devices when not in use. (Network equipment makers and standards are indeed aiming to lower the baseline power of internet routers, since network standby is an EU-regulated mode for energy efficiency.)
  
• Network Infrastructure & Traffic Patterns: The environmental impact of the network infrastructure itself goes beyond the electricity for data transmission. Manufacturing and deploying network equipment (fiber optic cables, 5G towers, data center servers) has an embedded carbon footprint. A broadcast OTA network is relatively static – a finite number of transmitters and antennas, upgraded infrequently. An OTT delivery ecosystem involves constant growth and replacement: new data centers, more servers, edge CDN nodes, new generations of Wi-Fi and cellular tech. While our focus here is mostly on use-phase energy, a comprehensive sustainability analysis would consider these life-cycle impacts. Another factor is traffic timing: internet streaming traffic peaks in the evening when many users watch, which can strain electricity grids as well (data centers and network gear draw more power at peak load). Broadcast has a constant transmission load, but viewing peaks don’t greatly change transmitter power draw (though people using TVs at night means residential power usage goes up then too). There is research into scheduling large data transfers during off-peak renewable energy times – for example, pre-downloading popular OTT content to local caches or even to users’ devices during times of surplus green energy. Such strategies (sometimes called “demand shaping” for data) could make OTT delivery more grid-friendly, though this is still an emerging concept.
  
• Content Delivery Models – Push vs Pull: OTA broadcasting is a “push” system – content is sent out regardless of who watches. This can lead to wasted transmission (if few watch a given program, the transmitter doesn’t know that). OTT is a “pull” system – content is only sent when requested, which is inherently efficient in not delivering data no one asked for. However, OTT often involves repeated deliveries of the same content at different times to different people. For example, consider a popular drama that 10 million people watch on broadcast at 9pm – OTA sends it out once to reach all of them. In an OTT scenario, those 10 million might stream it over the course of days or weeks on demand, resulting in the episode’s data being transmitted millions of times individually. Unless mitigated by caching, this repetition uses more data transfer and server processing. Caching helps – OTT providers cache content on servers closer to users (ISP nodes) so that after the first few viewers in an area stream a show, subsequent viewers get it from a nearby cache (saving long-distance data travel). Peer-to-peer distribution could also reduce duplicate data (an area of research and some niche implementations). The net effect depends on usage patterns: if everyone binge-watches the show in the first 24 hours, OTT can approximate a one-to-many efficiency by caching; if viewership is long-tail over months, there’s more redundancy in delivery. Broadcast, however, can’t provide on-demand access – if you missed it, you either record it or use catch-up OTT anyway. In summary: streaming avoids broadcasting unused content, but introduces repeated transmission of popular content. Hybrid approaches (like multicast OTT for live events or pushing on-demand content during off-peak to local devices) could combine the strengths of both models.
  
• Quality and Data Impact: OTT streaming often gives users the choice of streaming in HD or Ultra-HD (4K), which dramatically increases data rates (and hence energy per hour) compared to standard definition. An HD stream might be 5 Mbps (~2.25 GB/hour) whereas 4K can be 15-25 Mbps (~10+ GB/hour). Higher bitrate means more work for networks and likely more power consumed in data transfer and decoding. OTA DTT in the UK currently mostly broadcasts HD at up to ~9-10 Mbps per channel, with no widespread 4K broadcast due to bandwidth limits. Thus, a user watching in 4K HDR on OTT is using much more data (and energy in networks) than any current terrestrial broadcast viewer could. Efficient video compression is crucial for both: newer codecs like HEVC, AV1, and VVC promise 30-50% reductions in bitrates for the same quality, which directly translates to energy saved in distribution (fewer bits to transmit, fewer disk reads in a data center, etc.). Streaming platforms have been quick to adopt modern codecs and even per-scene encoding optimizations to minimize bits. Broadcast standards move slower (DVB-T2 in UK improved efficiency over older DVB-T, but future upgrades might be needed to broadcast in UHD efficiently). Audio/video codec innovation is a big opportunity for sustainability – every bit reduced is energy avoided along the chain.
  
• Emissions Intensity & Energy Sources: As mentioned, switching to renewable energy sources for powering both OTT and OTA infrastructure is a huge lever for reducing carbon footprint. Broadcasters and telecom operators in the UK have already moved in this direction: for instance, Sky (pay-TV and OTT provider) reports 100% renewable electricity for its operations, Arqiva (broadcast network) 99% renewable for its transmitters, and BT (which carries a lot of OTT traffic over broadband) 100% renewable for its networks​. This means that even if streaming or broadcasting uses a lot of electricity, the associated emissions can be very low if that electricity is green. Internationally, companies like Google (YouTube) and Netflix also purchase renewable energy and invest in offsets to claim carbon neutrality for their data usage. However, using renewables doesn’t reduce the physical energy consumption – using less energy in the first place is still important for easing strain on power grids and achieving climate goals (since renewable capacity is not infinite and should ideally displace fossil uses elsewhere). Moreover, not all parts of the world’s internet or broadcast infrastructure are greened yet, so efficiency improvements have global benefit.
  
• E-waste and Device Turnover: Another sustainability aspect is the manufacturing and disposal of devices and equipment. OTT’s rise has meant consumers buy new smart TVs, streaming dongles, and upgrade phones regularly. The embodied carbon in these electronics (minerals mining, manufacturing, shipping) can actually outweigh the use-phase emissions for some devices if the device has a short lifespan. Broadcast TV also has device impacts (TV sets, antennas, etc.), but one could argue a basic antenna and TV might be used for a decade or more. On the other hand, constant network upgrades for OTT (new routers, data center hardware) also contribute to e-waste. An environmentally sustainable approach would encourage longer device lifespans, software updates to keep hardware current, recycling and responsible e-waste handling, and perhaps modular or upgradable equipment to avoid full replacement frequently. For example, if a TV can last 8-10 years but its streaming app platform goes obsolete in 3, a small streaming stick can extend its smart life at low power cost, which might be better than scrapping the whole TV for a new model.
  

In summary, sustainability is not just about the energy used in one hour of streaming vs broadcast – it encompasses user choices, device design, network build-out, and even content strategies. A holistic view suggests that no single factor makes one technology universally “greener”; rather, how we manage and mitigate each factor will determine the overall environmental impact. Next, we’ll look at what the broadcasting and streaming industries are doing (and aiming for) to address these challenges in line with climate targets.

Aligning with Climate Targets: Goals for a Sustainable Future

The climate crisis has led countries and industries to set clear emissions reduction targets, and the media distribution sector is no exception. In the UK, there is a legally binding target to reach net-zero greenhouse gas emissions by 2050, in line with the Paris Agreement’s global objectives. That means every sector – including broadcasting and digital streaming – needs to decarbonize its operations and supply chains. Here’s how the broadcast and OTT industries are aligning with sustainability goals and what targets they are pursuing:

• National and International Targets: The UK’s net-zero by 2050 mandate (and intermediate carbon budgets) provide a timeline for cutting emissions. Additionally, many organizations aim to hit milestones much sooner. For instance, the BBC (British Broadcasting Corporation) has set an ambitious goal to achieve net zero emissions by 2030 for its own operations​. This encompasses reducing direct emissions (from offices, studios, company vehicles) and indirect emissions from electricity (by using renewables), as well as tackling its extensive supply chain (which includes everything from TV production to distribution). Other UK broadcasters like ITV and Channel 4 have similarly committed to climate action plans (often in the 2030–2035 timeframe for significant reductions) as part of a broader industry effort. Internationally, streaming giants are also on board: Netflix announced it achieved net zero greenhouse gas emissions in 2022 (through a combination of reductions and investing in carbon offsets/nature-based projects) and pledged to halve its emissions by 2030​. Amazon (Prime Video) and Disney have corporate climate pledges (Amazon aims for net-zero by 2040, Disney by 2030 for direct operations). These targets align with or exceed government mandates and reflect stakeholder pressure for climate responsibility.
  
• Energy Efficiency and Emissions Reduction: To hit these goals, both broadcasters and OTT platforms are focusing on reducing energy consumption and switching to clean energy:
  
  • Renewable Energy: As noted, companies are moving to 100% renewable electricity for powering studios, data centers, transmission sites, and offices. Broadcasters like the BBC, ITV, Sky, and international media companies have joined the RE100 initiative (committing to 100% renewable power). Telecom operators (whose networks carry OTT content) also have targets – e.g., BT in the UK is targeting net-zero (including its supply chain) by 2040 and already uses renewables for all its UK operations​.
    
  • Efficiency Programs: Broadcasters are investing in more efficient transmission equipment and cooling systems for their technical infrastructure. For example, upgrading an old transmitter to a newer model can significantly cut electricity use for the same output. Likewise in data centers, OTT providers and CDNs focus on server efficiency (higher workload per server, efficient cooling, etc.). Some streaming data centers even use waste heat recovery or locate in cold climates to reduce cooling energy.
    
  • Carbon Accounting & Science-Based Targets: Media organizations are measuring their carbon footprints in detail. The DIMPACT project (convened by Carnstone, mentioned in the Ofcom report) is one example, where streaming and media companies collaborate to quantify the emissions of digital services across the value chain​. This helps identify hotspots and track improvements. Many companies have set science-based targets (aligned to limiting warming to 1.5°C) which often means cutting emissions ~50% by 2030. Achieving this will require not just cleaner energy but also reductions in energy use – hence the push for efficiency and possibly new distribution models.
    
  • Network Provider Collaboration: Broadcasters and streamers are increasingly working with network operators to reduce overall footprint. For instance, the BBC, ITV, Channel 4, BT, and Arqiva formed a partnership (through the Carbon Disclosure Project) to decarbonize broadcasting together, recognizing that collaboration is needed for scope 3 emissions​. Similarly, streaming companies work with cloud providers (like AWS, Google Cloud) to ensure their services run on carbon-neutral infrastructure.
    
• Content & Scheduling Initiatives: In addition to tech-focused goals, some broadcasters consider changes in content delivery scheduling to save energy. For example, there have been discussions about static overnight lines-ups: if fewer people watch TV at 3am, perhaps some transmission could be reduced or switched to a low-power mode. However, public service obligations often require a 24/7 service. Still, creative approaches like consolidating channels in off-hours (fewer multiplexes active) or encouraging use of on-demand for late-night niche viewing could be explored to cut transmission energy. Broadcasters also use their platform to educate and encourage sustainable behavior (the BBC and others incorporate green themes in programming and have internal policies via BAFTA’s albert initiative for sustainable production).
  
• International Cooperation: The drive for sustainable broadcasting/streaming is global. European broadcasters through the EBU (European Broadcasting Union) exchange best practices on energy management and have working groups on sustainability. The streaming industry, being global, often aligns on standards – for instance, standardizing how to measure a “gCO₂ per streaming hour” to track progress. There’s recognition that if one country moves all TV to OTT, the upstream impact might be felt on international CDNs and cloud servers, so a holistic global approach is needed.
  
• Targets Beyond Carbon – Water and Ecology: While carbon is the main focus, some leaders in the industry are also considering broader environmental targets. Data centers use water for cooling, so OTT companies might target water-use efficiency. Networks and broadcast sites occupy land and can impact local ecology (though many transmitter sites are actually small footprints and sometimes even havens for wildlife due to restricted access!). Some broadcasters have “nature positive” goals (as the BBC’s plan includes biodiversity alongside net-zero​).
  
• Policy and Regulation: Thus far, environmental performance is mostly self-driven by industry and corporate social responsibility, as regulators like Ofcom do not yet impose carbon requirements. However, regulators have started to pay attention – e.g., Ofcom did this study to inform the debate. It’s possible that in the future, energy efficiency standards or reporting for streaming could become a part of regulatory oversight (some have suggested “energy labels” for streaming/video services, analogous to energy ratings on appliances).
  

In essence, the broadcast and streaming industries are increasingly making sustainability a core objective, setting targets that echo national climate commitments. The goals often coalesce around a few key themes: cut energy use, use green energy, and innovate to deliver content in new, low-carbon ways – all by 2030–2050 timeframes. Meeting these goals will require not just internal changes by individual companies, but also cross-industry cooperation and technological innovation. Fortunately, a number of promising initiatives and industry alliances are already leading the charge on greener video delivery, as we’ll see next.

Driving Sustainability: Initiatives and Industry Leaders

Transitioning to sustainable streaming and broadcasting is a challenge that no single player can solve alone – it spans content creators, broadcasters, OTT platforms, network operators, and tech vendors. Here we profile some of the leading proponents and initiatives from both the OTA and OTT ecosystems working to reduce environmental impact:

• Greening of Streaming: A new industry-wide initiative (founded in the UK in 2021) specifically aimed at making OTT streaming more sustainable. Greening of Streaming brings together companies across the streaming value chain – its members include big names like Akamai (a major CDN), Intel and AMD (chip manufacturers), DAZN (sports streaming platform), the EBU (European Broadcasting Union, representing broadcasters), and many others​. The goal is to “put a laser-focus on ensuring OTT can fulfill its sustainability duties”​. This group facilitates research, shares best practices, and encourages eco-design in streaming technology. For example, they explore efficient video delivery protocols, ways to prevent energy waste during streaming (like reducing buffer bloat and avoiding unnecessary video streams), and how to optimize networks end-to-end. The inclusion of both streaming companies and broadcasters (EBU) in Greening of Streaming underscores that even broadcasters investing in OTT want to ensure the shift doesn’t increase carbon footprints. DAZN’s involvement shows pure streamers are keen to improve their green credentials too.
  
• BBC and UK Broadcasters: The BBC, as a public service broadcaster, has taken a leadership role in sustainability. Internally, the BBC has a dedicated Sustainability team and a comprehensive plan for net-zero by 2030​, which includes reducing distribution emissions. BBC R&D has conducted groundbreaking studies on energy use of distribution – e.g., a BBC white paper formed the basis of the Carnstone approach used in Ofcom’s report​. The BBC also co-founded initiatives like DIMPACT to measure digital media emissions. On the content side, the BBC’s “Albert” initiative (managed by BAFTA) has become an industry standard for sustainable TV production, and by extension it raises awareness of sustainability across everything broadcasters do. ITV and Channel 4 have their own sustainability teams and targets, and collaborate (despite being competitors) on initiatives like albert and CDP supply-chain projects. These broadcasters are looking at things like: more efficient encoding and multiplexing for DTT, energy management at transmitter sites (some transmitters now have smart controls and monitoring to optimize power), and rationalizing infrastructure (for example, sharing masts and facilities between broadcasters to avoid duplication). Arqiva, which operates most of the UK’s broadcast towers, is a key player – by sourcing renewable electricity and improving transmitter hardware, it has greatly reduced the carbon intensity of OTA delivery. Arqiva is also forward-looking: it has started a “broadcast-grade streaming” project​, which aims to bring the reliability and efficiency ethos of broadcasting into the streaming world. This could yield solutions like multicast streaming or more resilient OTT platforms that avoid waste.
  
• Telecom & CDN Companies: On the OTT side, much of the heavy lifting is done by telecom networks and CDNs. Companies like BT (Openreach), Vodafone, Virgin Media O2 in the UK provide the broadband pipes. They have programs to improve network energy efficiency (such as BT’s trials of more efficient routing hardware, turning off parts of the network during low usage, etc.). Akamai, which carries a huge portion of global internet traffic (including for Netflix, etc.), has been a pioneer in transparency and efficiency – it publishes an annual sustainability report, has targets to power servers with renewables, and is constantly optimizing server algorithms to deliver more bits per watt. Akamai’s membership in Greening of Streaming shows its active role. Google/YouTube operates one of the largest content delivery infrastructures and has been carbon-neutral since 2017 (through offsets) and aims for carbon-free energy 24/7 by 2030. Google also designs its own servers and networking gear for efficiency and has pushed the envelope on video codecs (developing VP9, AV1, etc.) which help reduce data usage globally. Netflix similarly built out a global CDN called Open Connect, placing efficient caching appliances inside ISP networks to cut down transit energy. Netflix’s corporate sustainability includes not just operational carbon neutrality, but also funding nature conservation to offset residual emissions​. Amazon Web Services (AWS), which underpins many OTT services and runs Prime Video, is committed to 100% renewable energy by 2025 and has an initiative to become “water positive” by 2030 (important for data center cooling).
  
• Device and Technology Vendors: The devices we use – smart TVs, streaming sticks, set-top boxes, mobile devices – are made by companies like Samsung, LG, Apple, Amazon (Fire TV), Roku, etc. Many of these companies have their own sustainability initiatives (e.g., Apple and Samsung both have carbon neutrality goals and have improved the energy efficiency of their products over generations). There is ongoing innovation in chips: for instance, Arm and other chip designers focus on low-power processors that decode high-definition video with minimal energy. The latest TV models often boast better energy ratings due to more efficient LEDs and local dimming. Regulators in Europe have even set power consumption limits for TVs to push manufacturers toward efficiency (which sparked controversy around 8K TVs potentially exceeding limits – a debate balancing innovation vs. energy). Set-top box standards in the EU and US now include power-saving features and auto-sleep modes; these were driven by industry consortium agreements to reduce the whopping energy that cable/OTT boxes used in the 2000s. The IEEE and ITU also have working groups on energy-efficient ICT (Information & Communication Technology), which indirectly affect streaming (for example, better standards for energy management in Ethernet, Wi-Fi, and 5G networks help reduce power draw for data-heavy services).
  
• Collaborative Research Projects: Beyond corporate initiatives, there are academic and cross-industry research efforts. The LoCaT Project (mentioned in Carnstone’s report) analyzed GHG emissions of delivering TV content across Europe, giving insight into different countries’ distribution footprints. The EU has funded projects on ICT energy efficiency (like Horizon 2020 programs focusing on network energy optimization and green data centers). The International Energy Agency (IEA) has been studying the footprint of streaming and debunking myths, providing guidance on real vs exaggerated impacts​. Such research helps stakeholders focus on effective strategies (e.g., IEA highlighted that streaming’s footprint, while growing, is still modest and manageable with efficiency gains​).
  
• Consumer-Facing Initiatives: Some efforts involve directly engaging viewers. For example, energy labels on consumer electronics help buyers choose efficient TVs (EU energy labels now consider HDR and realistic usage). Streaming apps could in the future display an eco-indicator (there’s nothing mainstream yet, but conceptually a service might show how much CO₂ a download or stream might emit, to nudge users to HD instead of 4K if they don’t need it). Education campaigns by public broadcasters sometimes include tips like turning off devices at the wall, or downloading content on Wi-Fi (which tends to be more efficient than cellular streaming, plus different energy profile). While such tips currently aim more at data cost saving, they have environmental benefits too.
  

Leading by example: The convergence of broadcast and OTT is also yielding collaborations – e.g., the 5G Broadcast trials (BBC and partners tested broadcasting TV over 5G signals, which could one day allow phones to receive broadcasts efficiently) or hybrid TV standards (HbbTV, ATSC 3.0) that blend OTA and broadband. These efforts, while technical, are driven in part by the idea of “best of both worlds” – using broadcast where it’s efficient (one-to-many) and broadband where it adds value (interactivity, on-demand) in a seamless viewer experience. If successful, such hybrids could prevent unnecessary duplication of streams (thus saving energy).

All these proponents – from big broadcasters to streaming giants to tech suppliers – are crucial to making video delivery sustainable. The encouraging news is that the industry is mobilized: sustainability is on the agenda at major conferences (NAB, IBC now have “green” panels), and alliances like Greening of Streaming show a willingness to cooperate on this pre-competitive issue. But continued innovation will be needed to handle the ever-growing appetite for video in an eco-friendly way. That leads us to consider what’s on the horizon for greener video distribution.

The Road Ahead: Innovations for Sustainable Video Distribution

What does the future hold for the sustainability of TV and streaming? As we look forward, a mix of technological innovation, creative rethinking of delivery methods, and policy support will likely shape a lower-carbon future for video. Here are some key innovations and opportunities on the horizon:

• Next-Generation Broadcast Technology: Broadcast standards are evolving to become more efficient and versatile. For example, the DVB-T2 standard (already in use for HD terrestrial TV in the UK) is far more spectrum- and energy-efficient than earlier DVB-T. Further evolution like DVB-I (an internet-friendly broadcasting standard) could allow content to be delivered by whatever method is most efficient at the moment (OTA or OTT) without the user noticing a difference. In the US and some other countries, ATSC 3.0 (NextGen TV) is being rolled out – it’s an IP-based broadcast system that can support 4K and even datacasting. ATSC 3.0 could broadcast data updates to many devices simultaneously (even push VOD content or software updates during off-peak hours), potentially reducing the need for each device to fetch those over broadband. 5G Broadcast is another emerging tech: it uses cellular technology to broadcast video (e.g., live TV) to many phones or cars at once without each one needing a separate stream. Trials in Europe have shown it can deliver linear TV to mobile devices very efficiently. If widely adopted, 5G Broadcast could offload popular live streams from unicast networks, saving energy when say millions are watching the same live event on their phones.
  
• Smarter Streaming Protocols: On the OTT side, much innovation is happening in streaming protocols and network management to improve efficiency. Traditional HTTP-based streaming (HLS, DASH) is simple but can be improved. Multicast-ABR (Adaptive Bitrate) is a concept where the network can switch to multicast mode for popular OTT streams (like live sports), sending one stream to serve many users at an ISP level, then your home router simply splits it to your devices. This brings bandwidth and energy savings in the last-mile network. Companies are working on reliable multicast solutions for the internet (one challenge is ensuring quality of experience with encryption, etc., but progress is being made). Peer-to-Peer (P2P) streaming is another idea: if a few neighbors are watching the same Netflix show, their devices could share chunks directly, reducing duplicate fetching from distant servers. Some video platforms have experimented with P2P delivery (especially for live events where many local users watch concurrently). While P2P uptake is limited so far, it remains a potential way to reduce backbone traffic.
  
• AI and Optimization: Artificial intelligence is being applied to optimize various parts of the chain. For example, AI-driven video encoding can achieve the same visual quality at lower bitrates by intelligently allocating bits or even predicting what the viewer pays attention to. This could cut data sizes significantly. AI can also help in network routing – dynamically routing streams via the most energy-efficient path or server. There’s research into “carbon-aware routing”, where networks could route data through regions where electricity is currently green (high solar/wind output) and avoid data centers on dirty backup power. Though data isn’t as easily rerouted as electricity, large cloud providers can shift loads between data centers to some extent. If a video processing task (like transcoding a library to a new codec) can be done in a time/place where renewable energy is abundant, that lowers its carbon footprint.
  
• Improved Caching and Edge Computing: Content Delivery Networks will continue to push content closer to users, which reduces the distance data travels and often reduces energy in the core network. Edge computing might see small servers in every neighborhood or 5G base station, storing popular videos or even handling live transcoding for local needs. This hyper-local delivery could cut latency and energy. Additionally, active cache management – predicting content demand and pre-fetching content during off-peak times – can ensure that when you hit play, the content comes from as nearby (and efficiently) as possible. Some OTT providers already pre-position content (e.g., Netflix’s Open Connect appliances inside ISP networks, or Amazon pre-loading Prime originals on ISP caches before release).
  
• Energy-Proportional Hardware: One issue today is that many network devices and servers consume nearly the same power when idle as when busy. Future designs aim for energy-proportionality, meaning energy use scales with workload. If at 3am the streaming load is light, an energy-proportional CDN server or router would downclock or turn off some circuits to use less power. Data center operators are working on this (e.g., putting servers to sleep quickly when not needed, without harming responsiveness). Even in broadcast, transmitters could theoretically lower power at night if coverage requirements are relaxed (though that’s not standard practice now). More adaptive power management across the board can eliminate waste.
  
• Greener Codecs and Formats: As mentioned, video codecs are key. The next few years will likely see AV1 become common (several streaming services already use it on supporting devices; YouTube and Netflix heavily use AV1 which is ~30% more efficient than H.264). VVC (H.266) and AV2 are on the horizon with even greater compression gains, though they need more processing power (so a balance between device energy and network energy must be struck). There’s also interest in scene-aware encoding – e.g., not all scenes need full resolution or frame rate; if metadata could guide streaming to dynamically adapt (beyond today’s crude resolution steps), data could be saved. On the audio side, delivering surround sound to a mobile phone is wasteful – new standards might allow dropping channels or using simpler audio coding when high fidelity isn’t needed, saving a bit more.
  
• Holistic System Design: A more radical innovation avenue is rethinking the overall system architecture. For instance, what if future TVs come with more built-in storage and intelligence to cache content proactively (like how DVRs recorded shows, but expanded to streaming)? If tonight 1 million people will watch a new episode on iPlayer, the system could quietly cache it to their smart TVs in advance (perhaps transmitted overnight via a broadcast or a multicast download) so that when they press play, no internet streaming is actually needed – it plays locally. This kind of “pre-positioning” content merges OTT and broadcast concepts, and could drastically cut peak-time streaming load. It requires predicting what users want (or at least pushing popular content). Another concept is inter-device coordination: our homes have many screens; they could coordinate to use energy optimally (e.g., if the big TV is on, maybe it becomes a hotspot to feed content to a tablet rather than both pulling separately from the internet). These are experimental ideas, but as IoT and home networks advance, they become more feasible.
  
• Consumer Empowerment & Settings: Empowering users with more control and info can also help. We might see streaming apps offer “eco” settings – e.g., a toggle to prefer lower resolution when on mobile data (some already default to that) or an option like “data saver” which not only saves data cost but is framed as eco-friendly. Netflix had a feature to let you cap data usage per hour. If users understand that streaming in 4K on a small screen is wasteful, they might opt for 1080p and not notice the difference, halving data. UI Nudges might include warning a user if they are streaming ultra-high bitrates but network conditions indicate it’s mostly wasted (some apps already adapt automatically, but user-set preferences for quality sometimes override).
  
• Renewable Integration & Energy Storage: On the power side, there’s innovation in pairing data facilities with renewables and batteries. Imagine a future Netflix server node at a wind farm: it caches popular shows and only runs high-load tasks when surplus wind power is available. Or telecom exchanges with solar panels and on-site battery that carry evening streaming powered by the daytime sun stored. These setups can ensure that even if energy is used, it’s not drawing from fossil-fueled grids. Some broadcasters are exploring energy storage at transmitter sites (e.g., batteries or even hydrogen generators) to provide backup and possibly to load-shift grid usage.
  
• Shutting Down Legacy Systems: An often overlooked but significant opportunity: sunsetting old, inefficient legacy platforms. Maintaining multiple parallel delivery systems is inefficient. For instance, if a country still runs analog TV (some do), that’s an obvious candidate for switch-off to save power (the UK already did this in 2012). In radio, replacing power-hungry medium-wave or long-wave broadcasts with digital (or internet) can save energy (the BBC has been turning off some of these old transmitters recently to cut carbon). In TV, eventually if/when streaming can fully replicate broadcast reach (including for older and less affluent audiences), a discussion will be had about turning off terrestrial broadcasts to save energy and spectrum. However, that only makes sense if the streaming alternative is efficient and accessible to all (or perhaps replaced by a next-gen broadcast that is more efficient). Some estimates suggest keeping an under-used DTT network running could become inefficient by the 2030s if audiences plummet, while others argue keeping DTT until it can be replaced by an equally efficient multicast OTT is prudent. Coordinating transitions to newer tech (like all-IP delivery or new broadcast tech) will be crucial – do it too early and you force people onto potentially higher carbon options; do it too late and you waste energy on an under-utilized system.
  
• Policy and Incentives for Green Streaming: Looking ahead, governments might introduce incentives or regulations: for example, encouraging telcos to report energy per data volume, or setting efficiency targets for data centers (the EU is looking at this under its Green Deal). Even something like a carbon tax on electricity could indirectly push streaming providers to minimize energy use (since it would affect their costs). On the consumer side, energy labeling for streaming services or content could be a nudge (though it’s tricky to implement). The idea of “digital carbon footprints” might become mainstream, with individuals tracking the footprint of their digital activities much like they do for travel. If so, services that can advertise a lower carbon per hour (perhaps through efficient infrastructure or renewables) might have a marketing advantage.
  

In summary, the future offers a toolkit of innovations – from advanced tech (AI, new protocols, 5G broadcast) to systemic changes (hybrid delivery models, content pre-caching) – all aimed at delivering more video with less energy and carbon. The exact path will depend on business decisions and cooperation among stakeholders, but the trajectory is toward convergence and efficiency: broadcast and broadband technologies melding together to give users content seamlessly while minimizing waste.

Conclusion: Towards Net-Zero TV – Everyone’s Role

The sustainability of video streaming vs broadcast is a nuanced topic, but a clear picture emerges: there’s no simple winner across the board, yet enormous potential for improvement in both. Today, OTA broadcast has an edge in energy efficiency for mass viewing, and OTT offers flexibility but at a higher energy cost per viewer – however, with smart engineering and greener practices, OTT can be made much more efficient, and broadcast can evolve to be more flexible, meeting in the middle.

Both forms of delivery are already relatively low-carbon per hour (on the order of tens of watt-hours, or only grams of CO₂, per viewer-hour), especially as electricity grids decarbonize. The bigger challenge is the scale: billions of hours are watched globally, and streaming traffic is skyrocketing. Without intervention, the cumulative energy use and infrastructure emissions will grow substantially. But as we’ve explored, the industry is far from complacent – from the UK to the world stage, media companies, tech firms, and regulators are actively working to ensure our entertainment needs don’t conflict with our climate needs.

For broadcasters and OTT platforms, the path to sustainability involves innovation, collaboration, and commitment. They should continue to:

• Invest in efficiency at every level (data centers, networks, devices, codecs).
  
• Embrace renewable energy and even help fund new clean energy projects to power their services.
  
• Collaborate through groups like Greening of Streaming, DIMPACT, and industry alliances, to share solutions and avoid siloed approaches.
  
• Educate consumers gently about the impact of their viewing choices and provide tools to stream more efficiently (without sacrificing quality unnecessarily).
  
• Align business incentives with sustainability, so that what’s good for the planet (like reducing bits transmitted) is also good for the bottom line (lower bandwidth costs).
  

Policymakers and regulators, while supporting the growth of digital media, can encourage transparency and set standards that nudge the sector toward greener operations – for example, requiring large streamers to report energy use, or protecting spectrum for efficient broadcasting until/unless an alternative is proven greener.

And what about us, the viewers? While this lesson focused on industry actions, individual choices do add up. Simple steps like using an energy-efficient TV, turning off devices when not in use, streaming over Wi-Fi instead of mobile data when possible (Wi-Fi on fiber is generally more efficient than 4G/5G on a per-GB basis), or downloading content for offline viewing (to avoid re-streaming the same things) can all make a small difference. Even being mindful of streaming in ultra-high definition on devices or for content that doesn’t benefit from it can save energy (for instance, watching a talk show in 4K vs 1080p has no real viewing benefit but uses much more data). These are minor sacrifices, if any – often they go unnoticed in terms of experience but help reduce waste.

Ultimately, the goal is that we don’t have to choose between enjoying our favorite shows and caring for the environment. The question “OTA or OTT – which is more sustainable?” might eventually become moot as the two converge and as both approach net-zero emissions operation. The broadcasting and streaming industries are aiming for the same end-point: carbon-neutral content delivery that supports global climate targets while meeting consumer demand. This journey will likely transform how content is delivered, yielding a future where, for example, live events reach us via intelligently managed networks that minimize duplication, and our on-demand binges are powered by green energy and smart distribution.

In conclusion, sustainability in media distribution is a shared responsibility. The technology is rapidly evolving to meet the challenge – from more efficient networks to innovative hybrid delivery. The companies involved are increasingly aware and proactive, as we’ve seen with numerous initiatives. With continued effort, streaming and broadcasting can both be part of a climate-friendly media ecosystem, allowing us to stay entertained and informed without costing the earth.

Whether you’re a broadcast engineer, a streaming platform executive, or an avid viewer, consider sustainability in your relationship with media. Small decisions (in design or in viewing habits) scaled across millions can have a big impact. As an industry professional, ask how your organization can optimize energy use or collaborate on green tech. As a consumer, signal to providers that you value eco-conscious practices. By doing so, we all help ensure that the future of television – however it’s delivered – aligns with the future of our planet. Let’s tune in to a net-zero future, where our love for video is truly sustainable.