Photo Credit: Jiazi (Flickr)
Clean technology can boost energy efficiency, reduce waste, and save Washington State billions of dollars annually, while developing a competitive advantage in a multi-trillion dollar industry. Here’s a sample of some significant strategies to make this happen. You can learn more about just how much waste we create in Washington and the economic cost to our state in Part 1.
Some quantity of wasted energy in our industrial society is inevitable and unavoidable. 1 However as me move towards greater electrification of end-uses and develop new technologies the opportunity to minimize energy waste and boost efficiency grows significantly. Let’s review some opportunities already available today to reduce wasted energy & carbon while strengthening the economy.
Do you have ideas for other waste reduction technologies? Leave us a comment describing your waste reduction idea below or get in touch with us directly.
1. Electric Vehicles:
A typical gas powered internal combustion engine is only 20% efficient at converting gasoline into mechanical energy (e.g. forward movement), with the rest of the fossil fuel energy wasted as heat. By contrast, an electric vehicle is typically around 70% efficient at converting wall outlet power to mechanical energy. 2 Taking into consideration transmission and distribution losses from the power plant to the wall of 6-7%, and a notional efficiency of 90% for hydro-generated electricity, an EV “fuelled” by hydropower has a total efficiency of roughly 60%. This represents a tripling in efficiency (20% to 60%) while slicing transportation energy waste in half (from 80% wasted to 40% wasted). Unsurprisingly, this also translates to significant fuel-cost savings. Even with low gasoline prices of 2015, the fuel cost per mile driven is roughly 2.8 times more for a gasoline vehicle. This can vary greatly year to year due to gas price volatility, with prices projected to rise into the future. In 2014, it would have cost roughly 3.8 times per mile to fuel a gasoline vehicle than a comparable electric vehicle while July 2018 prices are around 4.2 times greater per mile for gasoline. Electrifying transportation in Washington, with its relatively low electricity to gas price ratio, leads to greatest fuel cost savings of any state (DOE e-gallon). Applied across all transportation usage, the fuel cost savings of electrifying transportation in Washington translate to roughly $4.5 billion dollars in 2014 and $3 billion 2015. That’s enough to buy outright over 100,000 electric vehicles per year at an average purchase price of $30,000. By contrast only 32,000 EVs sales in Washington state are estimated from 2011 through April 2018 (ATV scoreboard). On a household basis, the Department of Commerce reports that 68% or $3,440 of 2014 household energy expenditures were for Vehicle Transportation, meaning the average household could achieve fuel savings of roughly $2,200 to $2,600 per year by going electric.
2. Electric Heat Pumps:
A heat pump can replace a building’s natural gas or oil furnace. While fuel-fired furnaces are around 80-95% efficient, seemingly very good, heat pumps are often advertised as having efficiencies of 300% or more. 3 Although a thermal efficiency greater than 100% is impossible, this conversion of useful energy efficiency speaks to the point that the useable input energy (electricity) is smaller than the useable heat output the heat pump delivers. 4 Despite the complexity of describing their efficiency, heat pumps represent another great opportunity for Washington to reduce energy waste. A heat pump with even a relatively low COP of 2 (200% useful efficiency, well below Energy Star ratings) 5 powered by a hydroelectric plant requires half of the energy input to produce the same amount of useable heat as a fuel-fired furnace. Even with current natural gas prices much lower than historical norms and future projections, the cost per unit of heat delivered from natural gas is comparable to a 200% “efficient” heat pump though there is more waste and pollution associated with the later. 6 Heat pumps will also reduce the quantity of electricity used to heat homes that use conventional electric heaters, despite those heaters having nearly a 100% thermal conversion efficiencies as essentially all of the electricity used is converted into heat. A recent Rocky Mountain Institute (RMI) report noted that in most locations new builds with heat pumps are a lower lifetime cost option than natural gas heating, and in some areas this holds true even for retrofits (Electrifying Buildings for Decarbonization, 2018). This also includes heat pumps for water heating. According to the RMI study, a natural gas water heater uses 3.7 times more energy than a heat pump system no matter the location or whether it’s a retrofit or new building.
3. Thermal Power Plants:
The power sector itself is another big opportunity for efficiency improvements and reduced waste. Coal, Oil, Nuclear, and Natural Gas power plants all operate by converting fuel into thermal energy and then that thermal energy into electrical energy via various heat engine designs. On average thermal plants in the U.S. operate with fairly low thermal efficiencies, as indicated by LNNL applying a 33% conversion efficiency to all thermal power plants. For Washington, the existing Natural Gas fleet convert fuel to electricity more efficiently than the Coal Power fleet serving Washington load, at 43% and 33% conversion efficiency, respectively. 7 Shifting dispatch to favor existing natural gas over coal would reduce energy waste, and appears to be a readily available option (E3 study link?). Another option is modernizing aging power plants to combined cycle gas turbines which would increase power plant conversion efficiencies to 60%, creating a significant reduction in waste from the power sector. However, as power plant investments tend to lead to long infrastructure lifetimes, any net energy waste savings in the short-term will be cancelled out to the extent that new plants increase the overall use of thermal power plants at the expense of lower waste options, like Renewable Power Generation.
4. Renewable Power Generation:
Renewable energy sources like wind, hydro, and tidal offer an entirely different value proposition as they use generators (electric motors run in reverse) to convert mechanical energy into electricity. Generators typically have very high conversion efficiencies, exceeding 90%. In these applications any waste from the turbines themselves only leads to lost renewable energy which typically does not have a “fuel” acquisition cost like that of fossil fuels, meaning little economic waste. Solar photovoltaics and concentrated solar systems have lower conversion efficiencies, but also do not have fuel inputs or acquisition costs meaning likewise little direct economic waste. There is a big economic difference between wasted, free incident solar energy hitting a panel but not converted into useable electricity compared to coal being mined, processed, and transported only to be wasted as heat.
5. Industrial Combined Heat and Power (CHP):
Rather than just focusing on reducing waste through improved efficiency, another opportunity is to more fully utilize the wasted heat energy from power production. Thermal power plants are large stationary devices that produce a tremendous amount of waste heat. Many countries actually capture that waste heat in water, or steam, and distribute the thermal energy via a network of pipes (District Hot Water Systems) for residential and commercial building heat, hot water, snow-melt, greenhouses, and many industrial processes. Downtown Seattle has such a facility delivering heat to downtown residents and businesses. Every unit of otherwise wasted thermal energy utilized for end-use energy services reduces the quantity of fossil fuel or other energy form that needs to be converted, with associated waste, to provide that same energy service. In Washington, our electric sector produces over 200 trillion BTU’s of waste heat each year, similar to the BTU’s of natural gas used by all of our residential and commercial buildings. This currently wasted thermal energy could likely provide the bulk, if not all of, the thermal heating demand created by residential and commercial buildings if we had the proper distribution network and geographic locality of power plants
6. Micro CHP:
Developing a network of underground hot-water pipes connecting thermal demand to our power-plants waste heat is feasible, but is no longer necessary to take advantage of CHP technology. Small-scale commercial, and even residential, micro combined heat and power systems are now entering the marketplace. These emerging micro-CHP’s allow building owners to produce electricity on-site from natural gas and then directly use nearly all of the waste heat directly for their own building heating purposes. These make sense for waste and pollution reduction where a building is already using natural gas for heating and drawing electricity from a grid with non-trivial levels of fossil fuel generation. Micro-CHP units typically operate as a heater, responding to thermostat control. When turned on they start generating electricity until the waste heat that process creates delivers the necessary thermal demand to the building. The micro CHP opportunity is analogous to developing nations that skipped the installation of telephone wires because they could leapfrog to cell phones and avoid the wire infrastructure all together. While the efficiency for generating electricity in a micro-CHP is much lower than a traditional power plant nearly all the thermal waste output is being utilized creating very high thermal efficiencies that can exceed 90%.
While electric vehicles are more efficient, hybrids still avoid waste and may do so more cost-effectively and over a wider range of vehicle types than are offered as EVs. Hybrids also represent an interesting example regarding efficiency losses. Otto heat engines, or gasoline engines, burn more or less energy largely based on the revolutions per minute (RPM) they are turning. Different RPM’s lead to different fuel efficiency. Despite the conversion loss of using a gas engines to generate electricity, charge batteries, and power an electric motor in a hybrid, the electric motor saves more energy in avoided fuel by keeping the internal combustion energy running at high efficiency than all the energy lost due to the multiple conversions. With congestion continuing to be a major issue in urban areas, cars that actually are more efficient in stop and go traffic, like hybrids, may even prove to have greater fuel savings than advertised.
8. Insulation and Weather Stripping:
Homes in Washington are expending unused heat energy into the atmosphere as a result of poor thermal building envelopes, and heat from water pipes and hot water tanks that are poorly insulated. While it is far sexier to put a solar panel on you roof many homes could save significantly more energy at a far lower cost by better insulating their attics, walls, floors, windows and general weatherstripping.
9. Distributed Generation:
While electric motors, generators and basically all electronic devices are relatively efficient compared to diesel and gasoline motors, there is still transmission loss associated with transporting electrons from the power plant to the energy user. Expanding transmission lines is likely an important part of integrating intermittent renewable energy producers. At the same time distributed energy can reduce transmission loads, and wasted heat energy loss, by generating electricity at the point of consumption one of the big advantages of commercial and residential solar photovoltaic and hot water systems.
It is generally more popular to talk about technological improvements and cleaner energy than shifts in habits. However, it is important to also recognize the tremendous amount of waste that can be avoided through conservation. Conservation is the reduction in end-use energy services (e.g. home & water temperature, lighting quality, passenger and freight miles travelled), as opposed to trying to achieve the same level of energy services more efficiently. Putting in LED light bulbs is an example of an efficiency improvement, turning off all your lights when you leave your house is conservation. Turning down your thermostat, programing a smart thermostat, driving less, shutting off your computer, tv, stereo are all examples of conservation. The waste reduction potential of conservation is substantial, and best of all there are no upfront costs and implementation leads to immediate economic savings. Given the preponderance of transportation energy waste in Washington, and the associated costs and emissions, one particularly important opportunity is the reduction of vehicle-miles-travelled (VMT). This can take many forms, which vary in terms of ease of implementation, cost-effectiveness, and co-benefits created depending on the timing, location, and management of implementation. Strategies to reduce VMT may include: Shifting to higher average occupancy of vehicles (moving from single or low occupancy vehicles to carpooling, public transit ridership vanpooling); Freight logistics optimization; Mode shift to non-motorized vehicles (biking and walking often enabled by better routes or increased population density), and; Implementing workplace strategies to reduce the number of days commuting (such as work from home, or 4 x 10 hour workweek instead of 5 x 8 hour). Reduced VMT also has a direct impact in reducing congestion, making it easier and more predictable to go places when the need is greatest.
Many more opportunities to reduce energy waste exist today, and even more will exist tomorrow given focused policies and incentives that discourage energy waste and encourage efficiency, conservation, and innovation in our society. Let us know your ideas to reduce waste by describing it in a comment below, or reaching out to us directly.