Welcome to the Solar Decathlon at the National Mall in Washington, DC. It's a competition between 20 universities to build the best house powered entirely by the sun.
These modular buildings were designed, financed and constructed by students and advisers. Then they were transported and assembled on the National Mall to make a solar village.
Contestants are judged on 10 factors, including architecture, efficiency and market viability. They also have to charge electric cars.
Caption text by CNET.co.uk's sister site News.com Senior Writer Martin LaMonica.
Credit: Martin LaMonica/News.com
The winner of the last two competitions in 2003 and 2005 was the University of Colorado at Boulder.
This year, the team is focusing on modularity and flexibility. They built a house according to the competition's specifications -- sized about 74 square metres -- but the design allows it to be expanded to 204 square metres, the size of a typical family home, according to the project's student lead, Chad Corbin, who is pursuing a master's degree in building systems.
Corbin and his cohorts have worked on the structure for months -- Corbin himself has spent more than a year and half on the competition.
On Thursday of last week, only hours before the tours started, Corbin and his colleagues were still assembling the house. "I'm going on three or four hours a sleep a night, and me and another guy pulled two consecutive all-nighters," he said.
Credit: Martin LaMonica/News.com
Like many houses in the competition, the University of Colorado at Boulder built their houses around a 'core' that houses all the building systems -- lighting, heating and plumbing.
Additional rooms can be added to that core, giving builders and architects flexibility in where they can use the design.
Student team leader Corbin said he expects that the house could be used in high-end residences in the country, in urban environments and even for temporary housing.
That's because the core of the house is a metal shipping container -- the part of the building painted red here. Built around that are additional rooms and outdoor space such as decking and the garden.
Credit: Martin LaMonica/News.com
The 20 houses on the Mall need to run entirely on the sun and perform normal household tasks, such as running appliances and supplying hot water for washing dishes and laundry.
All of the buildings use both solar-photovoltaic (PV) panels that convert sun to electricity and solar-thermal systems that make hot water. All of the homes also have batteries to store electricity for when the sun isn't shining.
The Georgia Institute of Technology, with its 'Icarus' house, took a novel tack on solar photovoltaics.
It has three rows of solar panels on the roof that have motors that change the angle of the panels to maximise the amount of sunlight that comes in. Team members also chose to build a 'solar wall' covered with solar PV.
Credit: Martin LaMonica/News.com
Members of the Georgia Institute of Technology's team actually invented something new for the Solar Decathlon competition: a system to cool off solar-photovoltaic panels.
By spraying mist onto the panels (the water is stored rain water), they can increase the efficiency of converting daylight to electricity.
The white panels on this roof and the shelving on the walls of the building are there to provide shading (as do the solar panels). That's important because the roof and walls are made of a translucent material called an aerogel.
The aerogels are very good insulators to keep heat or cool air in. But in the summer months, shading is needed to prevent the house from getting too hot -- and consuming excess electricity.
Credit: Martin LaMonica/News.com
Another invention to come out of the Solar Decathlon are louvers that are covered with solar cells that generate electricity.
The Technische Universitat from Darmstadt in Germany created these 'building-integrated photovoltaics' and is said to be pursuing a patent.
Credit: Martin LaMonica/News.com
The competitors from the Technische Universitat Darmstadt in Germany have sought to create a house that is not only energy-efficient but is also efficient with interior space.
They have built-in cavities on the floor where home features can be put in, such as speakers, shelves or this hole for a bed.
The school used cutting-edge products like vacuum insulation. There are also materials in the wall that turn from solid to liquid as they are heating, which provides a way to store solar energy.
Credit: Martin LaMonica/News.com
The University of Santa Clara, which is competing for the first time in the Solar Decathlon, has made a house meant to fit in with the architectural style of California.
For the interior, the team used a sustainable material in a new way: the beams in the living room are made of bamboo.
Bamboo is often used in green homes for flooring because it grows quickly, is hard and can be stained a wide variety of colours.
Credit: Martin LaMonica/News.com
Where computer technology meets building technology. One of the equipment rooms in Santa Clara University's solar house is the control point for centralising data from 120 sensors in the house.
The sensors can automatically detect and adjust lighting, temperature and other factors. The students wrote software that gathers the information and displays it on a graphical user interface.
The program tells residents how much power they are consuming at a given moment and, when compared with typical homes, an idea of how much greenhouse gas emissions they are offsetting by having a solar home.
Another high-tech touch from a Silicon Valley university are 'electrochromatic windows' that darken to shade light automatically during hot times. The house will be used back on campus after the competition for research and for public education.
Credit: Martin LaMonica/News.com
Perhaps not surprisingly, many of the student teams chose a 'green' theme either as an inspiration concept or as part of the construction.
The University of Maryland built the 'LeafHouse'. The green wall, like the green roof, on the building is practical because it provides insulation. It's also meant to convey a connection between the indoor and outdoor space.
The south-facing roof holds the solar-photovoltaic panels and the evacuated tubes, which use the sun to heat water.
Credit: Martin LaMonica/News.com
Carnegie Mellon University built a 'greenscape', which collects rain water to nourish a series of plants on the front of the house.
The house also features an artistic installation in the back that uses plants to represent how the environment can change from global warming, depending on which path the planet takes.
Credit: Martin LaMonica/News.com
The Carnegie Mellon University team built a 'plug and play' house structured around a steel frame.
Rooms like this living room can be bolted on easily, according to students. That design allows residents to make changes to their house over time, such as adding rooms.
This house, like many in the competition, has a sophisticated data collection system that enables residents to see their energy consumption and generation. The students wrote a program to display the information and to automate lighting and cooling.
Credit: Martin LaMonica/News.com
The houses are not just judged on energy efficiency. Market viability and attractiveness are also part of the judging, where interior design and lighting play a role.
The Carnegie Mellon house uses high windows to maximise daylight and energy-efficient lighting. Residents can also adjust the colour of their lighting. All lighting can be controlled from a central switch.
Credit: Martin LaMonica/News.com
The Solar Decathlon is a competition to showcase the latest in energy technology, and green architecture and engineering. But the students also managed to have some fun with it.
The University of Texas at Austin used an energy-efficient hot tub as part of its construction.
For the Texas environment, the hot-tub idea is actually practical, according to architecture student Matt Weaver, who worked on the house. In Texas, excess heat is generated that can be used for the hot tub.
Credit: Martin LaMonica/News.com
Although it's the Solar Decathlon, the team from Texas A&M University decided to use wind power in its home. These small turbines feed the house's battery bank for storing electricity.
Credit: Martin LaMonica/News.com
Although the competition features the latest technology and results in new innovations, simple design choices go a long way, say participants.
Here, Texas A&M University places its evacuated tube solar collectors next to a pool of water, which reflects light to increase the hot water the tubes can heat.
Credit: Martin LaMonica/News.com
Public education is a big part of the Solar Decathlon. This is the University of Cincinnati's entry, which, like many houses, features plaques for public tours, seen here going up the ramp and deck.
Much of the information is geared toward children. Even before the event opened publicly, there were a number of field trips.
Credit: Martin LaMonica/News.com
Cornell University, which came in second place in the Solar Decathlon two years ago, used a metal truss structure for its house.
The design can hold the energy components of the home -- the solar-electric panels and hot-water collectors -- and can hold plants for shading. The structure is aimed at being flexible.
Credit: Martin LaMonica/News.com
US Secretary of Energy Samuel Bodman spoke at the opening ceremony of the Solar Decathlon on Friday. Afterward, students from the different teams -- these students are from Cornell University -- met the secretary and had their photo taken.
Assistant Secretary of Energy Efficiency and Renewable Energy Andy Karsner, standing at the podium, also spoke at the opening ceremony.
"I have to confess that being part of the Solar Decathlon is, in my experience, one of the best things about being energy secretary," Bodman said during his speech. "These houses, which are the result of your hard work, are all marvels of engineering and design, of creativity and innovation."
Credit: Martin LaMonica/News.com
Visit reviews.cnet.co.uk for in-depth reviews of many more products
