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World Environment Day

World Environment Day is the biggest annual event for positive environmental action and takes place every 5 June. ‘Connecting People to Nature’, the theme for World Environment Day 2017, implores us to get outdoors and into nature, to appreciate its beauty and its importance, and to take forward the call to protect the Earth that we share.

The day isn’t just a day to read about the problems affecting the countryside, it is all about action and physically getting off your chair to do something to help preserve nature.

“We can enjoy nature year-round, but World Environment Day is when the whole world comes together to celebrate our beautiful planet,” said Erik Solheim, the head of UN Environment. “It reminds us of what a treasure nature is, and encourages us all to protect and appreciate our environment.”

We can implement our commitments to substantially cut carbon emissions and support investment in renewable energy, and support for programs delivering policies and actions to adapt and build resilience to the impacts climate change.

“ But man is a part of nature, and his war against nature is inevitably a war against himself’.’- Rachel Carson”

A Passive House Takes An Active Stand For The Environment

About an hour’s drive north from Boulder’s city center, a passive house comprising of a small cabin-like structure sits nestled tightly between three healthy Ponderosa pines. Its south face, with seven giant triple-pane windows, overlooks Rocky Mountain National Park and lets in rays of wintery sunshine. Andrew Michler, the building’s mastermind, architect, and builder, calls this 1,200-square-foot space home. With unmistakable pride, he also claims it’s Colorado’s most energy-efficient house.

The building is, in fact, Colorado’s first internationally certified “passive house,” or, according to Michler, a house built according to a “globally-recognized building design technique that promises huge cuts in energy use.” By using super-tight insulation and thick south-facing windows — trademarks of the passive house — Michler’s home relies almost entirely on its natural surroundings for its electricity, heat, cooling, and water.

He doesn’t pay a gas bill; the sun does the work instead of oil. A 1,500-gallon rainwater catchment tank supplies all non-potable water. All of the electricity flowing through the sockets also comes from the sun. When it’s too hot inside, Michler simply opens the windows or blows air through a series of tubes that he installed underground, so as to let the earth cool down the air before diverting the streams inside. Altogether, Michler’s house consumes about 90 percent less energy than his neighbors.

“The passive house works surprisingly well in Colorado,” Michler says, due in part to the state’s 300-plus days of sunshine. However, it’s not just the sun that makes the off-the-grid house almost completely self-sustaining; its calculated structure and layout also play vital roles in its efficiency and success.

The wool-insulated walls — made of natural, durable, recyclable materials — are completely airtight, which allows Michler to precisely and reliably control the indoor air quality and temperature. The triple-pane windows are designed to maximize solar gain and minimize energy loss, so the sun can effectively heat the house, even in the dead of winter. This unseasonably warm snow season, Michler only employed an external heating unit once, when the internal temperature dropped below 62 degrees Fahrenheit. (Outdoors it was minus 10).

Inside, Michler’s wife and two adopted stray cats, Serendipity and George, amble around the lightly colored wood living room. Inspired by Japanese tiny home architecture, Michler designed the whole house to be multi-functional, with movable, multi-use furniture, like the staircase with removable wooden storage boxes that can be used as tables or stools when guests are over.

“Most of the rooms flow together and can change use over time,” Michler says. “Depending on how many people there are, either two or 10 people, we can make everyone’s stay really comfortable.”

The passive house concept was born in the early ’70s by a group of experimental engineers at the University of Illinois. The 1973 OPEC Oil Embargo banning foreign petroleum exports to the U.S. (repealed by the Obama administration in 2016) had sent fuel prices skyrocketing and thrown household budgets in panic. Running the furnace harder and longer to heat drafty, cold houses was no longer a viable option. Thus, it fell upon structural changes in home building to combat the poor insulation and leaky windows and doors that made regulating warm indoor air nearly impossible.

The engineers at the University of Illinois pioneered a highly insulated building model they called the “Lo-Cal house” in 1976. The model, compared to the most-efficient design promoted by the Department of Energy at the time, projected saving 60 percent of energy consumption. A Canadian group of engineers caught on and rolled out an even more efficient “superinsulation house.” When solar energy entered the scene around the same time, William Shurcliff, a Nobel-prize winning physicist at Harvard, coined the term “passive house” to reflect the increasingly multifaceted nature of these high-performance buildings.

By the end of the ’80s, Shurcliff, who was as much concerned with helping household budgets as he was saving the planet from environmental disaster, summarized in the 1986 Energy Review what he considered the path of future building construction.

Passive houses should include five main principles, he wrote: thick insulation, airtight construction, prevention of moisture accumulation, steady fresh air supply, and optimum window usage. When U.S. conservation initiatives waned in the ’90s, Wolfgang Feist, a German physicist, built upon Shurcliff’s work, further refining the modeling and product design while sticking to Shurcliff’s original five-pointed framework. These points became the cornerstones of the modern passive house.

In 2015, space heating was the leading cause of energy use in residential homes, according to the U.S. Energy Information Administration. Initiatives like Michler’s passive house and like-minded projects are pioneering the possibility of major energy reductions in everyday homes.

The airtight seal around the house, while necessary for regulating temperature, also creates a prime environment for mold and condensation, hence Shurcliff’s concerns about moisture control and air supply. To avoid these issues, Michler installed an air-exchange system that uses two fans to circulate air around the house. Essentially, one fan blows out stale, used air and another fan sucks in fresh air from outdoors. Both streams pass over a mechanism called a heat exchanger located under the house, which ensures the heat from the indoor air can effectively transfer to the new air with no energy lost.

However, activities like cooking in the airtight space can be problematic, according to Michler. For appliances that need high-density energy, like a stove and his backup space heater, he uses a small amount of propane gas that he purchases when necessary. But food and gas particles can be released into the air and potentially linger. He teamed up with University of Colorado Boulder’s Indoor Air Quality and Health research lab to ensure he was creating a healthy, livable space.

Ryan Militello-Hourigan, a graduate student at CU Boulder working on the research team, visited the house last fall and conducted several experiments to test its air quality.

“We found that overall the house has very good air,” Militello-Hourigan says. “[Michler] was conscious of potential problems when he was building, and so he used healthy materials. The thing we did notice was that the overall air exchange rate was fairly low compared to conventional houses.”

Michler isn’t a formally-trained architect. Everything he knows is self-taught, accumulated over years of writing about and working in sustainable construction. In 2012, he finally decided he’d try and create for himself what he’d been eyeing in magazines and theory books for years. Only seven months after initially sitting down to plan his house, Michler broke ground.

“Our team was young, not age-wise but experience-wise,” Michler says. “There is tremendous pressure [when building a passive house]. You have to get everything just right. One or two things wrong can compromise the entire system.”

Michler spent most of the past three years building and refining his home, staying involved in every step of the process. He predicts his home cost about 10-15 percent more than a conventional home but was somewhat offset because he already owned the land, and the house created a much smaller footprint.

Last year his house received its certification from the German Passivhaus Institute. Building upon his acquired knowledge and riding the stoke of his success, Michler founded Passive House Rocky Mountain, an organization that now trains and supports architects, builders or anyone interested in constructing and certifying their own passive house along the Front Range. He envisions the possibility of schools, community buildings and many more homes transitioning to passive design, creating healthier spaces for future generations.

“I’m looking forward to seeing how far we can push the envelope, especially in trying to make [buildings] more affordable and beautiful,” Michler says. “Shelter is as much about comfort as it is [about] energy performance.”


Solar Windows: The Future of Zero-Carbon Buildings

The advantages of solar windows power as a source of clean, renewable energy seem obvious. Sunlight is abundant, free and, for all practical purposes, eternal. While the price of solar photovoltaic cells recently has plummeted and their efficiency has gone up, challenges remain around siting vast arrays of solar-electric panels and finding ways to integrate them into buildings and other applications.

Photovoltaic (PV) glass uses the same basic principle as solar panels that you see on roofs, but it is transparent. The technology used is known as thin-film, which simply means that the active PV layer is applied very thinly. Unlike conventional solar panels where silicon monocrystals are grown and sliced into wafers, thin-film technology vacuum-deposits a film onto a conducted glass layer.

Think about it:

If windows can generate electricity for use on site, the consumer would gain the advantages of free, non-polluting power and at least partial grid independence. The grid would reduce its reliance on fossil fuels, gain resilience and get relief from peak-use demands, which would slash greenhouse gas emissions. Solar windows would also be practically unnoticeable, meaning you could reap the benefits of solar power at home with a minimum of impact on you or the community around you.

Turning windows into solar collectors is the kind of disruptive technology that can revolutionize energy generation and consumption and contribute to a low-carbon energy future. Someday, buildings ranging from your own house to urban skyscrapers might generate much of their own electricity through innocuous luminescent solar concentrating windows.


Business Delegation Trip to Germany

Recently, I had the chance of being part of the business delegation to Germany. The delegation consisted of a group of selected representatives from Kenyan and Tanzanian solar engineering service providers, industries with the interest in alternative renewable energy supply, mini-grid operators and other companies looking for less expensive alternatives to their diesel backup systems.

The trip offered us a great opportunity to get in contact with relevant suppliers and to participate in discussions on state-of-the-art PV Hybrid & Storage System Solutions.

Now, we all know that Germany is a world leader in innovation. The energy and environmental technology industry in this country have been influenced by the political goal of ensuring that by 2050, 80 percent of the electricity produced in the German market will be generated from renewable energy.

Our site visits opened us up to see sophisticated energy storage solutions that can be adopted in our country. Yes, some of us are already there as our website indicates but there’s always room to do better. The first site visit was at a storage installation M5BAT at the University of Aachen

M5BAT is a hybrid of different battery technologies that optimally combines storage capacities for periods of seconds, minutes or hours, whereby the storage system is designed for a total storage capacity of around 5-megawatt hours (MWh). What’s special about M5BAT is its modular design, which combines different battery technologies in an optimum fashion.

This highly efficient and modular system offers a wide range of applications irrespective of location and therefore facilitates the integration of renewable energies.

In this initial phase, the M5BAT project is focusing on two particular aspects:

  • Testing the distributed provision of control reserve for stable grid operation
  • Electricity trading and the associated exploitation of electricity price arbitrage

See you in my next blog post. Stay Tuned!

“Travel is more than the seeing of sights; it is a change that goes on, deep and permanent, in the ideas of living.” – Miriam Beard