System Optimization

Energy for buildings and transportation make up more than 70% of our carbon footprint. (UCLA Institute of the Environment and Sustainability) Any measures we can take to improve the efficiency of building systems, or reduce the amount of vehicle miles will have an impact.

Vehicle Miles Traveled (VMT)

In 2014, the transportation sector in Los Angeles County accounted for 37% of GHG emissions, (CARB) and according to the American Lung Association, that same year Los Angeles County had one of the nation’s highest levels of ozone and fine particulate pollution.

Health studies show that exposure to diesel exhaust primarily affects the respiratory system and worsens asthma, allergies, bronchitis, and lung function. There is some evidence that diesel exhaust exposure can increase the risk of heart problems, premature death, and lung cancer.

Particulate Matter (PM)

Particulate matter is the term for solid or liquid particles.  Some particles are large or dark enough to be seen as soot or smoke, but most are fine particulate matter. Fine particulate matter is composed of very small objects found in the air, including dust, dirt, soot, smoke, and liquid droplets. Ninety percent of diesel particulate matter is fine – more commonly referred to as PM2.5 (less than 2.5 microns in diameter).

Since transportation is such a large component of our carbon footprint, reducing VMT becomes an important issue in overall planning. Mass transit projects, such as Eco-Rapid, with a potential ridership of 75,000/day can have a huge impact in reducing VMT.

The last stages of completing a continuous 51 mile bikeway along the LA River are in progress. We performed a rough analysis to understand the potential impact of the bikeway to reduce VMT. Using the Transit and Connectivity method, we estimated this could reduce carbon emissions by 10,000 metric tons over 20 years, or 500 metric tons per year.

Photo by LADOT Bike Blog [CC BY-SA 3.0 (], via Wikimedia Commons

GHG Fact

  • 5% increase in walkability = 32% increase in active travel and a 6.5% reduction in VMT (2016 SCAG Active Transportation Report)

Water Delivery

One of the largest uses of energy in the state of California is to convey water from remote locations using the State Water Project, Los Angeles Aqueduct, and Colorado River Aqueduct. Much of the water conveyance energy use occurs outside the county. Detail studies of this energy requirement have been performed by groups such as the Arid Land Institute.

Under the topic of Water Recharge, we presented a concept for centralized water recharge in the San Fernando, Central, and West Coast Basins. Using information from various sources1, we can calculate the carbon reduction from the potentially reduced water imports. The 45,000AF/year presented could represent a 25,000 metric ton per year reduction in carbon. Carbon reduction for proposed centralized recharge projects in the San Fernando Valley represent and even higher reduction, as the recharge methods are less energy intensive, and could yield 50,000 metric tons per year.