The Return of Pedal Power

Over the past three decades, the mobility pattern in S.E. Asia has undergone major transformation: from bicycles to motor scooters and now back to bicycles. According to Beijing’s transportation commission, pedal power accounted for 63% of trips in the 1980s. This figure dropped to less than 18% by 2014. Surprisingly, however, bicycle usage is making a resurgence in the form of bike sharing accessed through smart phone apps. Today in Beijing, population 11 million, there are 2.4 million shareable bikes with half the population being registered users. That’s 40 times as many registered users as in NY City’s large Citi Bike program.

Bike sharing is a fast-growing global phenomenon, pushed in part by Chinese enthusiasm. The key has been joining technology together with a young, highly educated entrepreneurial class. The boom in China arose primarily from the problem of university students repeatedly having their bicycles stolen. Four years ago, some of those students started thinking that maybe you don’t need to own a bike. Now they are some of the most successful Chinese entrepreneurs.

In China, unlike in France where bike sharing got its start, there are no set docking station scattered around a city. Just leave the bike when you get to your destination and lock it (by iPhone, of course). Because of GPS tracking software, this parked bike then appears on the phone app of other nearby subscribers looking for a bike.

The biggest bike sharing companies in China, which have rapidly mushroomed into billion-dollar businesses, are spreading to hundreds of cities around the world, including more than a dozen US cities. A big attraction of bike sharing has been the solving of the “last mile” problem: helping people get between public transit centers and home.

China’s government has been encouraging the development of the shared economy, using a combination of incentives and minimal regulation. In the bike sharing arena, this has made possible explosive growth but has also created problems, the biggest being the many broken-down, discarded and vandalized bikes. Repair efforts have not kept up with the growing heaps of trashed or broken-down shareable bikes. One of the large Chinese companies has developed a bike with a drive shaft rather than chain propulsion, airless rubber tires that can’t be punctured and a solar powered, GPS smart lock—all innovations to minimize the need for repairs and to reduce thievery.

The growth of bike sharing in Europe and America has taken place in a more regulated environment and thus has been slower and more controlled. Because of convenience, health benefits, and improving infrastructure, biking and bike sharing will continue to expand. The public benefits—reduced carbon emissions, less pollution, less urban land dedicated to asphalt and a stronger community connectivity—are further spurs to the growth of pedal power.

Instant Hot Water with Less Waste

Hot water is typically the second largest use of energy in a home (after space heating and cooling). Despite its resource intensity, the hot water delivery system is seldom an area of focus when constructing a home. As a result, many homes have systems that take minutes to deliver hot water to the faucet and waste large amounts of energy and water in the process. Approximately 10-15 percent of energy use associated with hot water is wasted in distribution losses.

A brief article appeared in The Independent a few months back promoting hot water recirculating systems as a way to save water. A recirculating system is a hot water line that loops throughout the house connecting to all the fixtures that use hot water before returning to the water heater. These systems usually have a timer that runs a pump during fixed periods of peak hot water usage. By continuously circulating hot water during peak periods, it provides instant hot water and saves water by eliminating the water that typically runs down the drain while waiting for hot water to arrive. Water is saved but only by using an excessive amount of extra energy.

Another drawback: the pipes tend to fail prematurely (usually in 5-6 years) by corrosion from the continuous flow velocity of the water and from the water chemistry—certainly an issue in Santa Barbara with our hard water.

Another more sustainable option is on-demand hot water delivery, a system that is compatible with tank or tankless water heaters and works with solar hot water units as well -the greenest option. At the push of a button a pump turns on, rapidly pushing the ambient temperature water out of the hot water lines and into the cold-water lines en route back to the water heater. This ambient temperature water, which is normally lost down the drain, is replaced by hot water. When the hot water reaches a distant fixture, a thermal sensor detects the temperature rise and quickly shuts the pump off.

By using the existing cold-water line as the return line, an on-demand delivery system can be easily and cost-effectively retrofitted in existing homes. Because of the thermal sensor, the system will not allow hot water to cross over to the cold-water line, thus ensuring that all cold-water faucets still have cold water.

Energy is conserved: approximately 30 seconds after pushing the button, hot water arrives at the faucet and the pump shuts off.  Water is conserved: there is no cold water flowing down the drain while waiting for the hot water to arrive. The users are happy: 30 seconds after pushing the button, they can turn on the faucet and have nearly instantaneous hot water, while knowing that they are conserving water and energy.

Resilience in our Houses

Resilience in our Houses

Between 1955 and 1965 about 18 natural disasters occurred in the US annually. This decade, starting in 2010, we are averaging about 110 nationally declared disasters a year- roughly 2 per week. In the past, building codes were developed from historical data, but now State and Federal agencies are pushing communities to use predictive climate models to address more appropriately what’s coming.

Resilience is defined as “the intentional design of buildings, landscapes, communities and regions in response to vulnerabilities to disasters and disruptions to normal life.”

The local environment always plays a critical role in determining what makes a building resilient, or not. In other words, resilient design is always locally specific. Tapping into historic vernacular architecture, as well as local wisdom, knowledge and experience, often prompts strategies enabling buildings and occupants to better survive disasters. The big natural challenges we face in our region are droughts, wildfires, landslides, debris flows, intense precipitation, flooding, earthquakes and maybe even tsunamis. Resilience planning “is not about keeping people comfortable; it’s about keeping them alive” says Alex Wilson, President of the Resilient Design Institute. Preparedness includes planning for potable water, food, first aid, news and communication, toilet needs and getting around, probably without a car.

The 3 most important areas to focus on are:

Creating livable conditions for post-disaster. That means making your house (and surrounding space) wildfire resistant, constructing it to be seismically strong but flexible, and incorporating passive solar heating, cooling and natural ventilation. It is also important to provide protection from heavy rains with suitable roof overhangs, drainable planes behind siding, break-away panels, if in a flood plain, and infiltration swales and catch basins near the house.

Providing for back-up power. Evolve your home to be all electric with photovoltaic panels. Provide back-up power/storage for key electrical circuits in your home: refrigerator, cooking (if electric-magnetic induction), media, phone charging, electric car/bicycle, and a few lights. Avoid diesel generators. Battery back-up is increasingly affordable and reliable.

Accessing potable water. Develop a water supply, perhaps using rainwater collection, which can be filtered/purified with hand equipment to make it drinkable-safe. There are good filters pumps and ultraviolet portable treatment equipment available that were developed for wilderness trekking.

Doing all one can to stop, and even reverse, the climate crisis needs to be our top priority, but we also need to prepare for the disasters already arriving.

Fire Resistant Homes - New & Remodeled

No home is entirely protected against wildfire. Most have at least a few weaknesses, a few materials or openings that make them vulnerable to flying embers or to the intense heat of wildland firestorms.

Reducing this risk channels attention to a few fronts. Creating a 30’-50’ “fuel free” zone around a dwelling is mandatory: key steps to implementing this strategy are pruning up and thinning out trees; changing decks, trellises, fences, patio furniture and other flammable outbuildings to non-combustible materials; and removing all plant dead wood, wood piles and other easily ignitable materials. Stone, tile or concrete patios, metal or masonry fences, tube steel trellises and cementitious sheds near the house are worthy choices.

Shifting attention to the house, avoid wood or vinyl siding (susceptible to melting in high heat). Fiber-cement siding is a good choice, preferably with tongue-and-groove rather than shiplap joints. Stucco is also an excellent non-combustible covering option. Both materials have the added advantages of being rot and rodent proof, low maintenance, requiring infrequent or no painting.

Roofs need to be constructed with non-flammable underlayment on top of plywood sheeting, which is better than oriented strand board, a composite material commonly used. Superior roofing materials are tile, metal, cementitious composites and slate. Stay away from wood shingles or shakes, even when treated with fire retardant. Don’t forget to clean gutters regularly to maintain fire safety.

Double pane windows perform far better than single pane in resisting sudden spikes in temperature during wildfires and impact from wind-driven flying firebrands. Such spikes often cause window blowout. Smaller panes survive better than bigger ones. Wood, wood clad with aluminum, metal and fiberglass frames all perform well—certainly better than vinyl frames. All exterior doors should have a one hour fire rating.

Selecting high performance foundation, eave and attic vents is critical for creating a fire-resistant dwelling shell. Soffit and attic vents can be eliminated by using icynene insulation (an open cell foam) on the underside of the roof, the only code-approved way to do so. In homes with crawl spaces, foundation venting is required by code for moisture control. Baffle vents, auto-closing vents and 1/8” screened vents are recent developments specifically designed to protect vent openings from heat and embers. In wildfires, there are hundreds of thousands of flying embers driven far ahead of the fire front by strong winds. Most are small and go out immediately. The larger ones can get pushed into any opening in the house shell, where they can smolder for hours, until possibly igniting nearby combustible materials and burning the house down. 

Wildfires are important to the health and beauty of natural landscapes. Their periodic pattern reduces fuels, recycles nutrients, regenerates plants and stimulates biodiversity. We cannot “fireproof” forests, grasslands or shrub lands that depend on fire, but we can design, build and remodel homes to be more fire resistant.