Diagram of tiny house systems

WATER HEATING: A new eco-friendly and energy-efficient heat pump uses CO2 as a refrigerant, instead of standard synthetic refrigerants, to raise water temperature. ENERGY STORAGE: Using Tesla’s new lightweight and compact “Powerwall” lithium-ion battery, the house can store 6.4 kWh of energy and provide 3.3 kW of power. RADIANT HEATING: The heat pump works with a heat-exchange system to circulate water through the subfloor in a radiant heating system. ENERGY PRODUCTION: Eight photovoltaic roof panels collect enough sunlight to generate between 5-12 kWh per day. LIVING WALL: Water drained from the kitchen sink and shower flows through a “living wall” of plants and two feet of soil to remove organic contaminants before being filtered by activated carbon and disinfected by UV light. Processed greywater is then collected for bathing and non-potable reuse.

Eco-friendly tiny house

Could you live in a house smaller than the average American kitchen? An interdisciplinary team of Berkeley students thinks so. The group took two years to design and build a 171-square-foot, off-grid, eco-friendly house for a statewide competition sponsored by the Sacramento Municipal Utility District. The students spent the first year puzzling over how to allocate space for a solar energy system, lithium-ion battery, greywater recycling and a heating system — while retaining enough space for two people to eat, sleep, bathe, cook and live comfortably throughout the year.

“We’re balancing affordability with new technologies and making the house as energy-efficient as possible,” says applied science and technology doctoral candidate Kenny Gotlieb. Other team members represent the Energy and Resources Group, business, architecture, urban studies, public policy and public health. Judges will evaluate the house on architecture, energy systems, sustainable materials use and how the house manages water and waste.

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