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We are in 2030 and the Dutch neighbourhood Bospolder-Tussendijken (BoTu) is 100% carbon neutral. To radically reduce energy use, all household tasks are organised communally. Cooking, eating, doing the dishes, doing the laundry, showering, brushing teeth, going to the toilet: it all happens outside the individual household. Consequently, energy use in individual households has become so small that they can be disconnected, not only from the gas network but also from the power grid.
Image: Golnar Abbasi & Arvand Pourabbasi.
In the early 2020s, it was still assumed that all domestic tasks needed to happen within the walls of the individual household. But this is not how it works in other parts of the world, and it wasn't always the case in the Netherlands either. For example, in the second half of the twentieth century, Rotterdam counted hundreds of "water distilleries", where people came to fill buckets with hot water to wash their clothes.
Other household tasks have been organised in a communal way for centuries. Public bathhouses, community kitchens and bake ovens date back to Antiquity in many cultures. Washing clothes happened jointly at specific places and on specific days of the week. The BoTu neighbourhood was inspired by these traditions. Communal bathhouses, laundry rooms, kitchens and canteens are built on the main public squares, where the residents perform their household chores on a daily basis.
A Dutch "water stoker", distributing hot water to customers. Foto: Historische Vereniging Maassluis.
Communal Facilities = Larger Households
Communal facilities bring a lot of advantages. They free space in individual homes, which now only require bedrooms and living rooms. Consequently, more people can be accommodated in the existing building stock, meaning that households have become larger again.
In 1900, the average Dutch household consisted of 5 people, but in 2000 and in 2018 that had decreased to 2.3 and 2.1 people, respectively. This means that there need to be produced ever more kitchens, bathrooms, washing machines and tumble dryers for ever more households. That's good for the economy, but it requires a lot of extra energy, materials and money. Furthermore, larger appliances for communal provision are usually more energy efficient than the smaller appliances in individual households.
Low Energy Use in the Household
Because most household tasks are communal now, energy use in individual households has decreased significantly. The appliances that use the most energy, such as water boilers, cook stoves and refrigerators, are no longer there. Furthermore, the energy use per resident goes down as there are more people living in a household. For example, the energy use for the lighting does not increase linearly with the number of householders, because more people can enjoy the same light.
The electricity that's needed for lighting and electric appliances is produced on the spot. This happens either by the residents themselves operating exercise machines, or -- if the weather allows it -- by the solar panels on the roof of the building. The households only have a limited energy storage, which takes the form of a (shared) gravity battery that is built against the rear facade of the building.
Both the solar panels and the exercise machines are connected to a direct current low voltage electricity network in the household, which avoids energy conversion losses. If the residents don't feel like producing power on a cloudy day, they still have the option to light candles.
Heating
Most household tasks that require thermal energy -- cooking, showering, doing the dishes -- are organised and powered outside the household. This makes it easy to disconnect the homes from the natural gas network. The only exception is heating, which should also happen in individual households. In 2020, space heating was by far the largest use of energy in a typical Dutch household: roughly 60-70% of total household energy use.
Modern heating systems waste a lot of energy: they heat the entire air volume in a space in order to provide thermal comfort. Only a very small part of the energy is used to heat the people themselves. The heating in BoTu is based on a radically different approach: heating people, not spaces. In winter, people make use of suitable clothing (like thermal underwear) and personal heating sources (like warm water bottles and foot stoves). The foot stove is a small box with one or more perforated partitions, which contains a metal or earthenware bowl or pan filled with embers from the communal fireplaces on the public squares. The hot water for the bottles is also collected outside the household.
A foot stove. Image: Johan, CC BY-SA 3.0.
Many residents also chose for a traditional "korsi". This heating system, which used to be common especially in the middle east but also in other countries like Spain and Japan (under other designations), is a movable low table with a charcoal heater underneath. A thick cloth or quilt is placed over the table to trap the heat and the whole family slid their legs under it, sitting on the floor. Through its local heating effect, the korsi provides thermal comfort in an otherwise cool space.
Residents who are still cold, can jump into their box-bed (an insulated bed that traps body heat) or start producing electricity. Physical exercise is the best protection against the cold. Finally, the homes are insulated with carpets on the walls and on the floor, a much cheaper option than conventional insulation of building surfaces.
Next episode: The public bathing house.