Nina Lorkowski introduces readers to the technical and complex evolution of the bathroom, primarily in Germany. Far from the established fixture we think of today, bathing and bathing spaces went through a series of transformations from the late 1800s through the interwar period, especially as homes transitioned from using hard energy sources such as coal to gas and electricity. Drawing on an impressive wealth of sources from a range of archives, Lorkowski engages with a multitude of historiographies, including the histories of technology, energy, hygiene and medicine, gender, and consumption. Lorkowski argues for the importance of private households as users in the larger scholarship of energy consumption. As ideas about hygiene, bathing, and privacy all changed in the late 1800s, so did conceptions of the bathroom in the home. Still, interest in and use of new appliances and technologies did not always match planners’ and engineers’ intentions. In this compelling and technical study, Lorkowski brings contingency to the history of technological innovation in the home that has important implications for energy consumption in the context of greenhouse emissions and climate change today.

Divided into three main sections, the book proceeds primarily chronologically and examines its topic through the lens of three specific themes. The first section explores the evolution of bathing practices and spaces (“Bade Räume”), the second delves into innovations in technologies connected to the bathroom (“Von der heizbaren Wanne zum Durchlauferhitzer”), and the third section links the bathroom to energy networks, such as gas and the electrical grid (“Das Bad im Netz”). The first section is a history of how the bathroom—and the furniture within it—became a fixture in the home. The impetus for bathrooms coincided with and was the result of other late-nineteenth-century developments, such as an increased emphasis on bathing and personal hygiene as well as the expansion of a potable water infrastructure with connection to private residences. Everyday routines and practices evolved as water, especially heating water and then draining it, became simpler. Considering the different uses of water in the home (bathing, flushing a toilet, washing clothes, cooking, etc.), this section illuminates not only the practicalities of incorporating a bathroom into the home but forces readers to reexamine how the whole household functioned. Importantly, Lorkowski highlights class differences in access to these new technologies and their implementation in new construction, especially during the Weimar Republic.

In the second section, Lorkowski delves into technological designs and transformations surrounding devices used for heating water in order to bathe. Previously, people bathed in the kitchen where there was access to hot water from the stove, but now it became a matter of how to heat water in a designated bathroom. With useful images and sketches, Lorkowski highlights various methods that remain familiar today (hot water tanks and continuous flow heaters that use gas or electricity) as well as energy sources and designs that did not stick, such as petroleum and ethanol heating or solar heating. Lorkowski underscores the multiplicity of actors—architects, landlords, and builders—who all played a role in determining design, while home economics experts including housewives, medical professionals, and engineers debated the potential dangers and pitfalls of the various technologies. In doing so, the author reminds readers that incorporating new technology into the home was not always a foregone conclusion, for logistical reasons as well as cultural norms. Moreover, devices for heating water linked the private home to a larger network of energy supply, serving as an interface between the two.

The third section takes up precisely the question of where the private bathroom fit into larger gas and electrical grids, with a particular emphasis on Berlin in the 1920s and 1930s. Throughout this section, Lorkowski demonstrates how gas and electricity were in competition with one another for customers. Of course, expanded access to energy in the home changed habits and lifestyles, but Lorkowski also emphasizes that users had an impact on the development of the energy grid. Water heating devices were not only a consumer product and constituent part of household routines; they were also connected to a large-scale energy network that had limitations in terms of supply. Usage reflected demands on the networks, and not all aspects of the energy system grew at the same time or at the same rate. Nor were standards and norms clear early on. For example, Lorkowski shockingly relates how users sawed or filed off the ends of electrical plugs to fit in the socket (because lengths were not yet universal).

Warmes Wasser – Weiße Ware provides a compelling story of how the modern bathroom came to be and exposes the non-linear trajectory of that evolution. Lorkowski excellently incorporates gender, Alltag, material culture, consumption, and more into a rich and technical history of energy transition in the home. In a broad sense, the book is the pre-history of domestic energy consumption today and how it has become one of the mainstays of the energy industry. As the author notes in her conclusion, roughly a quarter of all energy in Germany is consumed by private households. With an eye toward reducing carbon emissions, Lorkowski reminds readers that technological innovation must work hand-in-hand with consumer habits, routines, and values to achieve climate goals. Ultimately, Lorkowski offers a deeply relevant reconsideration of domestic energy consumption that starts in the most private of spaces, the bathroom, but radiates through many facets of modern life.