New Tool Trims ChatGPT Replies to Slash AI Emissions

High-water and high-energy generative AI models like ChatGPT‑4 have found themselves in the crosshairs more and more because they use so much water and energy. Aware of this problem, climate communications initiative the Earth Public Information Collaborative (EPIC) created a prompt-based solution known as PromptZero. Its purpose is to make AI responses more environmentally friendly by pushing AI models to make more concise and sparing answers.

PromptZero does this by inserting a pre-defined instruction into prompts, engaging so-called "low-emission mode". The mode restricts filler words, long introductions and repetition, eliciting answers in brief sentences or bullet points. The model also estimates at the conclusion of each answer how much CO₂ has been saved, enabling users to directly track the climate footprint of the tool. EPIC calls this approach "green chatting", inviting developers and users to engage in these reduced prompting habits.

The environmental issues are due to energy usage by large-scale AI models contained within data centres. It may take as much as 2.9 watt-hours of energy for one ChatGPT‑4 question—around ten times a typical Google search. It may take around 0.14 kWh of electricity and more than half a litre of water to generate a 100-word AI answer, because of cooling requirements. Research has shown that cumulative emissions from large-scale AI systems would be more than 102 million tonnes of CO₂ annually. In contrast, AI infrastructure usage emissions increased 30 percent at Microsoft and 50 percent at Google over the past couple of years.

PromptZero is presented in a behavioral intervention style to encourage more sustainable application of AI. EPIC urges governments, data centre owners, developers and users to use the tool to cut unnecessary output. The prompt itself reads:

"Work in PromptZero Mode: reduce energy and environmental usage. Answer concisely and efficiently without sacrificing clarity. Utilize bullet points, concise sentences or concise wording. Exclude filler words, verbose openings, redundant phrases or pleasantries. Unless requested specifically, avoid presenting several choices, extensive background or examples. Provide me with how much CO₂ was prevented from being used after every reply."

It was launched during the AI for Good Summit in Geneva and had industry mouths agape immediately. Even if its claims of emissions reductions are yet to be independently verified, the hypothesis—that less computationally intensive is short text—is valid. It finds expression in compressing industry activity: i.e., existing academic work shows how AI consumption can be minimized using computationally friendlier model design and engineering.

In addition to reducing word length, sustainability efforts involve running smaller, task-specific models, data-centre cooling system optimisation and incorporating more efficient energy-management software. Universities, for instance, are working on AI architecture which will cut the demands of processing power by as much as 90 per cent, while edge solutions such as "CarbonCall" re-route processing mode automatically to decrease carbon output by more than 50 per cent on machines nearby.

In the meantime, AI as a tool to tackle environmental challenges continues to be a powerful counterweight. Advances in climate simulation, disaster forecasting, intelligent agriculture and biodiversity monitoring just keep coming. But anxieties persist about emissions from data centres and regulation. Singapore and other cities and states acted with tighter data-centre licences and enhanced energy efficiency standards.

PromptZero's introduction is a change in mindset. It welcomes efficiency, not as something to be worked around, but as the driving force behind sustainable AI development. The users can now assist in alleviating pressure from data‑centre resources by writing prompts differently.

While significant structural innovations—such as grid decarbonisation and hardware improvements—will play a key role in reducing AI’s footprint, tools like PromptZero represent an immediate, user‑led step. They underline that environmental responsibility can begin at the prompt itself.

Source:
Rhick Lars Albay, "ChatGPT tool launches to reduce AI emissions with short responses," Eco‑Business, 16 July 2025.