As the need to eliminate and even draw down greenhouse gasses, chiefly CO₂ and CH₄ , becomes ever more urgent, so too does the need for tools to generate renewable energy and simultaneously reduce our demand for it. Thermoelectrics tackle both problems: by definition, they can generate electricity directly from thermal energy, and through this process they could also recycle waste heat from our inefficient devices, which waste 50% of their energy as heat. Much research has gone into thermoelectric materials in recent years, but the need for conflicting materials properties, including a high electrical conductivity and Seebeck coefficient but a low thermal conductivity, have meant high efficiencies are restricted to materials consisting of rare and toxic elements, precluding their use in the volumes required. This thesis examines a number of potential earth- abundant thermoelectric materials. Through thorough observation of scattering sources for phonons and electrons, we discern if the materials will make effective thermoelectrics, and why. First we look at the effects of a complex structure, through BaBi₂O₆; and then take a more design-focused approach by looking at anion substitution to augment the transparent conducting oxide ZnO into Zn₂NX, X = Cl, Br, I. This allows the assessment of these design methods, and other emergent topics, so that still better thermoelectrics may be developed, perhaps in time to postpone the worst effects of the climate crisis.