SPONSOR CPD PROGRAMME Continuing professional development (CPD) is the regular maintenance, improvement and broadening of your knowledge and skills, to maintain professional competence. It is a requirement of CIBSE and other professional bodies. This Journal CPD programme can be used to meet your CPD requirements. Study the module and answer the questions on the final page. Each successfully completed module is equivalent to 1.5 hours of CPD. Modules are also available at www.cibsejournal.com/cpd Setting the standard for net zero buildings This module explores the drivers underpinning the call for net zero and considers the key points of the recently published ASHRAE Standard 228 With extraordinary climatic1 and oceanic2 events filling the headlines, arguments3 raging over the opening up of further North Sea oil reserves, the viability of carbon capture and storage remaining uncertain,4 and the global construction of low carbon offshore wind farms stalling,5 the time of the net zero building is undoubtedly here. This CPD will explore some of the key drivers behind desperate calls for net zero buildings, and provides an overview of the recently published ASHRAE Standard 228 which joins the increasingly congested knowledge space of how to guide and assure the swift move towards net zero built environments. The existential threat of climate change is all around us. July 2023 was confirmed as the hottest month since records began in the 19th century, as United Nations (UN) secretary general Antonio Guterres proclaimed: The era of global warming has ended. The era of global boiling has arrived.6 Buildings are considered an essential part in the overall plan to reduce anthropogenic impact in an attempt to steady the climate, since the burning of fossil fuels has emitted enough greenhouse gases to significantly alter the composition of the atmosphere and average world temperature has risen between 1.1 and 1.2C.7 The World Meteorological Organisation recently reported8 that the average global temperature in 2022 was about 1.15K above the 1850-1900 average (the benchmark period before the emission of greenhouse gases from human and industrial activities). Between 2023 and 2027, it is predicted to reach between 1.1K and 1.8K higher. Ninety per cent of the global warming occurs in the oceans, as has been measured9 in recent decades, causing the waters temperature to rise, so increasing its massive store of heat. The record-breaking 2023 temperature rises in the North Atlantic are seen as part of natural variation within the climate system coming together to elevate sea-surface temperatures, although Professor Albert Klein Tank, head of the Met Office Hadley Centre noted: It is not believed that these factors represent a climate-changeinduced tipping point that produces runaway temperatures. However, they will add to climate and weather impacts this year.10 In 2015, the UN Framework Convention on Climate Change (UNFCCC) adopted the Paris Agreement, which set a goal of limiting global warming to well below 2K preferably to 1.5K above pre-industrial levels. To limit global warming to 1.5K, greenhouse gas emissions must peak before 2025 at the latest, decline 43% by 2030 and reach net zero by 2050.11 To achieve this goal, the Paris Agreement, adopted at the 2016 UN Climate Change Conference (COP21), requires countries to submit their own national plans to reduce greenhouse gas emissions. However, seven years after the Paris Agreement some two fifths of the way to 2050 more than half the worlds nations have not been able to go beyond pledging a set of net zero policies, and nearly a quarter have no evidence of even having a proposal for net zero target (as shown in Figure 1). The 2022 UNEP report,12 released at COP27 in Sharm El Sheikh, reported that in 2021 the buildings and construction sector accounted for more than 34% of energy demand, and around 37% of energy- and process-related CO2 emissions, and that the sectors 2021 operational energy-related CO2 emissions were up 5% over 2020 and 2% over www.cibsejournal.com September 2023 71