While we’re hearing more often about net-zero energy buildings – those that produce as much energy as they consume – many of the projects are relatively small, such as a branch of TD Bank, the filming of the Avatar movies and a new community in South Carolina and an apartment building in Sacramento.
That’s about to change. San Francisco’s famed Exploratorium museum is moving to a new 333,000-square-foot campus and aims to achieve net-zero energy.
That’s an apt vision for a science museum that encourages a high degree of interactivity from its 560,000 annual visitors. If the organization succeeds with its plan, the facility will be the largest net-zero use museum in the US – if not the world.
Scheduled to open in spring 2013, the museum is tripling in size as its being re-located to a pier on the city’s iconic Embarcadero waterfront, with indoor and outdoor exhibits.
100% of its electricity will come from a 1.3-megawatt (MW) rooftop solar PV installation that’s already in place. An innovative heating and cooling system will draw on water from the San Francisco Bay – saving at least 2 million gallons of water a year compared to conventional buildings.
These technologies won’t be hidden behind-the-scenes, they will be showcased publicly – with live real-time energy use and solar PV production statistics on display in the lobby, updated every 15 minutes.
"This project combines an effort to both innovate and think critically about the impact science can have on the world. Our net-zero goal is, in part, a way to reduce our global footprint and help improve the community we’ve been a part of for more than 40 years,” says Dennis Bartels, executive director of the Exploratorium. “Net-zero is a process – and an opportunity for the public to learn with us.”
The museum expects that reaching and maintaining net zero status will "require monitoring and tinkering over the next couple of years."
"Exploratorium [officials] spent a lot of time ensuring that this happened," Joe Olla, in charge of marketing for the contractor, told ENR California. "They feel they can probably do LEED Platinum, but, candidly, they are much more interested in net-zero energy than anything. They feel providing a net-zero building of this magnitude is really the goal."
Here are some of the features the Exploratorium is relying on to achieve LEED certification and eventually reach net-zero energy:
- 5,874 high-efficiency solar panels from SunPower that generate enough power for about 1,000 average American homes; excess energy will be fed back to the grid
- An innovative Bay Water Heating and Cooling System will regulate indoor temperature – saving about 2 million gallons of water annually compared with typical evaporative cooling towers.
The technology works by pulling in bay water, filtering and cleaning it, and then pumping it through a heat exchanger. About 73,800 gallons of water will be circulated every hour.
- Waterless urinals and low-flow plumbing fixtures; 16% of the water from roof runoff will be collected and reused for toilet flushing with the rest filtered and returned to the bay.
- High-performance glass to reduce heat gain and take advantage of natural lighting.
- Recycled and low-emitting materials, along with certified wood are being used throughout.
- A ventilating system that uses 100% outside air with no recirculation, increasing energy efficiency and better indoor air quality
Net-zero energy buildings are expected to grow rapidly over the next 20 years, reaching almost $690 billion by 2020 and $1.3 trillion. It’s one of the big investment areas for venture capital for green building technologies.
Some of that is due to regulatory changes. In April, California Governor Brown issued an executive order that will transform new and renovated state buildings to net-zero energy.
In the European Union, near-zero energy buildings are mandated by 2018 for public buildings, and by 2021 for all construction.
But achieving net-zero energy status – or striving for it – is also viewed as a smart business strategy for new construction because it helps reduce operating costs and improve resource efficiency.
An example of this is a self-sustaining college campus being built in the California desert, which focuses on green building not just to reduce costs but to create a unique curriculum that attracts students and cleantech companies to locate there.
In 2010, the Dept of Energy awarded $76 million from the Recovery Act to support advanced energy-efficient building technologies, such as net-zero energy buildings.
Learn more about the Exploratorium: