Resources are dwindling, prices are rising, and energy efficiency has never been more important. Commercial buildings have long been designed with conservation in mind: Taiwan’s national stadium is covered almost entirely with solar panels, and the CaixaForum Museum in Madrid boasts a living wall of 15,000 plants. However, with the world’s population predicted to exceed 8 billion by 2050, architects are turning their green design skills to residential homes. Potential structures range from ancient mudbrick domes, to space-age Earthships. Some designs are more viable than others, but the Big Deal team have identified five of the most promising candidates. For a glimpse of the future, check out their infographic below.