An autonomous house is designed to use native resources to replace infrastructural support services such as electric power, gas, municipal water and sewage systems, systems, storm drains and others to reduce costs and environmental impacts.

Autonomous buildings follow the modern trends as well as the net zero energy buildings and share similar design and building technologies, such as:

• solar collectors for hot water generation and photovoltaic panels
• seasonal thermal storage in tanks
• solar cooling
• geothermal heat pumps
• in-wall and in-floor heating and cooling
• pre-heating and cooling of fresh air through central air-conditioning units

© Neill Lewis, chartered architect

Tour of  Zero  Energy House, built by Anthony Aebi of Greenhill Contracting

House owner – David Shepler,  IBM Research. The first home owner in Green Acres.

Video by IBM Social Media – David Shepler explains  his zero energy home functions:

Geothermal energy is one of the most important energy source in zero energy home.  Heat can be extracted from any source, even from the cold one, but naturally a warmer source provides higher efficiency.

Ona a small scale, for example for a family house, this can be performed using a geothermal heat pump. While an air source heat pump requires more energy, because it draws heat from the cold air from the outside, a geothermal heat pump uses ground as a source heat, so it takes advantage of surface ground temperatures which starts at 10  °C, 50 °F. Alternatively a ground water heat source can by drawned.

Ground based heat pumps do not cread any pollution, do not require any fuel and they work regardless of weather, bacause of the constant temperature of surface ground. However, once we´ve mentioned the advantages we have to mention the disadvantages too.

Operation of an air source heat pump is recommended only in mild temperate. As we mentioned, geothermal source heat pumps are more efficient, but compared to air sourced ones are far more expensive. Also, mainly in cooler climates a secondary heat source is needed.

Passive and zero energy houses that comply to the energy standard are built and used in many european countries, mainly in Germany, Austria, Switzerland and Sweden. But now, we would like to mention one interesing, energy efficient modular house concept from Estonia, called Elumaja.

The Elumaja concept combines several “energy efficient packages” or modules, called Base, Solar, Power, Water and Smart. Combining these packages,the final house can meet a passive house or even zero house energy standard.

Base – ventilation and heat-recovery element, electrical heating, electric boiler. This concept requires connection to external networks.

Solar – this package includes solar collectors used for hot water and gas tanks or small co-genetarion plants.

Power – including this energy package ensures, that Elumaja complies with the criteria of zero energy building. The Power package includes a solar power station, a battery pack, inverter, automatically triggered backup generator/co-generation plant and a control panel with visual output. Also a wind generator can by included. This package profides independence from electric grid.

Water – consists of rainwater collectors, water purifier and a separating and composting toilet and provides independence from water and wastewater networks.

Smart – enables to centrally manage the equipment for operating the building.

And what is the price of Elumaja zero energy house?

A 45 m² house starts from 63 300 EUR, and 135 m² from 159 100 EUR which is not really higher than the market average, when we consider that the Heating cost are just 0 EUR/year.

Elumaja houses use only environment friendly materials and materials that never pose health risks. The company avoid using materials whose production is energy intensive, materials based on oil products or non-recyclable materials.

While it is not so easy to achieve zero energy requirements in existing buildings, we can still focus on energy savings using  energy-efficient appliances.

We prepared a list of tips that can help you to reduce energy use in your home:

Building Envelope

Consider an Energy Audit
Seal Air Leaks
Insulate
Replace Inefficient Windows & Doors

Air Conditioning
Reduce Your Need for Air Conditioning

Heating
Decide Whether to Replace Your Existing System
Calculate Your Return on Investment
Improve the Performance of Your System, Old or New

Ventilation

Eliminate Pollutant Sources
Ensure Efficient Local Exhaust
Filter Out Particulates
Improve Whole-House Ventilation

Cooking
Use High-Conductivity Materials
Reduce your Cooking Time
Match the Pan Size to the Element Size

Refrigeration
Check Door Seals
Adjust the Thermostat
Move the Refrigerator to a Cooler Location
Minimize Frost Build-Up
Manage Your Food and Storage Space

Dishwashing
Avoid Hand-Washing
Wash Only Full Loads
Use Energy-Saving Cycle Options

Laundry
Optimize Load Size
Use Lower Temperature Settings
Reduce Drying Time

Lighting
Turn Lights Off and/or Install Sensors
Switch to LED Lights
Switch to Compact Fluorescent Lamps
Use of Natural Daylighting

Water heating
Fuel Choice and Sizing
Compare Life-Cycle Costs
Minimize Operating Costs

Do not forget that buying an appliance, you commit to paying  the operating cost for as long as you own it.