SIGNAL: Health Damage
The Health Damage data signal is an estimate of the damage to human life and health caused by emissions from electricity generation based on electricity used at a certain time and place.
Seven million people a year die from air pollution, and a lot of it comes from power plants. Fossil-fueled power plants emit air pollutants that damage health like sulfur dioxide, nitrogen oxides, and particulate matter. People downwind of power plants experience higher rates of health problems like asthma, heart disease, stroke, and premature death caused by breathing these pollutants.
Every time any device–from a small laptop to a powerful electric vehicle charger–draws power, at least one power plant on the local grid (the “marginal” generator) immediately ramps up to provide that energy. Which power plant is the one that responds changes throughout the day, and some power plants cause much more pollution and harm than others. So, using electricity at some times and places causes more harm than using it at other times and places.
Every time any device–from a small laptop to a powerful electric vehicle charger–draws power, at least one power plant on the local grid (the “marginal” generator) immediately ramps up to provide that energy. Which power plant is the one that responds changes throughout the day, and some power plants cause much more pollution and harm than others. So, using electricity at some times and places causes more harm than using it at other times and places.
What is it?
The Health Damage data signal is an estimate of the damage to human life and health caused by emissions from electricity generation based on electricity used at a certain time and place. The units of Health Damage are US dollars per MWh (based on the value of a statistical life).
How is it used?
The Health Damage signal can be used to make decisions that reduce negative impacts on human life and health. IoT and EV companies use the forecast of health damage as an input signal to their device scheduling optimization, or to create a UI element advising users when to run appliances or plug in an EV. It is often used in tandem with the Marginal Operating Emissions Rate to co-optimize device operation to reduce both greenhouse gas emissions and damage to human health.
Temporal coverage
- Granularity: 5 minutes
- Historical: At least 2 years in the past, published usually within 6 hours
- Forecast: +72 hours (rolling 3-day forecast), published usually within 1 minute
- Forecast (Historical): At least 2 years in the past
Geographic coverage
- Granularity: Health damage regions are typically balancing regions or subregions
- Coverage: WattTime’s Health Damage Signal coverage can be seen here
Methodology + validation
WattTime developed a model that estimates the health damage effects of using electricity at different times of day in particular locations. This is done by first determining which power plants are likely to respond to an increase in electricity use on a local grid and how much pollution they make. How much pollution reaches nearby areas is dependent not only on what fuel is burned but also on whether pollution control filters are installed (a relatively easy step that, when skipped, causes a lot of harm) and the height of the smokestack. All of these factors are accounted for by comibining WatttTime's MOER model with a separate model called INMAP. The number and distance of people who live and work downwind of the smokestack are considered to determine the number of premature deaths that are caused by the pollution coming from the responding power plants. The health damage effect changes throughout the day based on which power plants are responding to changes in usage on a local grid.