UK-based architectural firm John McCall Architects is redefining what it means to be energy efficient. The company recently won a Buildings & Energy Efficiency Award for a family home that only racked up a yearly energy bill of around $21. Even more impressive, the project, located in the English town of West Kirby, did not cost millions to complete.

How did they do it? According to the firm's website, the building "uses a combination of tried and tested construction techniques along with some modern heating and ventilation technology to give very good performance and exceptionally low running costs." For £240,000 (or approximately $341,000), the team designed the four-bedroom family home with insulated masonry, triple glazed windows, an air source heat pump (ASHP), and large solar panels on the roof.

In the two years the home has been occupied, its residents have racked up about 3453kWhrs of electricity each year from heat, lighting, water heating, and cooking. However, the solar panels have offset almost all of that by generating 3338kWhrs of electricity.

"This is a simple building and, in effect, runs on the same amount of power used by a 40W light bulb," designer and resident Colin Usher told the BBC. To learn more about the project, visit the John McCall Architects website.

Banner image via John McCall Architects on Facebook

[h/t: Inhabitat]