How Natural Gas Distributed Generation Makes Cities Safer (Part 2)Posted on February 14th, 2019
As we explained in Part 1 of this paper, the vulnerabilities and weakness of the transmission and distributions lines that make up the electrical grid leave cities susceptible to power problems and blackouts. Moreover, the low energy density of wind and solar energy systems increase a city’s dependence on the grid. Alternatively, generating electricity with natural gas Distributed Generation (DG) makes cities more electrically secure while reducing energy costs and aiding the decarbonization of the electrical industry. This second installment of a two-part paper summarizes why generating electricity with natural gas is not an option, but a practical and economic necessity, to increase the use of renewable energy resources and improve public safety.
Natural Gas Needed for More Renewables
The U.S. Energy Information Administration (EIA) reports that large-scale solar photovoltaic and wind systems only produce electricity on average about 25% and 35% of the time, respectively. The rest of the time, electricity must come from other sources. Historically, coal and nuclear generation produced most of the electricity needed to cover renewable energy shortfalls. In first half of 2018, natural gas became the indisputable primary energy source for electricity by generating 33% of the total U.S. kWhr compared to 27% and 20% for coal and nuclear, respectively.
Natural gas is a substantially cleaner fuel compared to coal and oil. Nuclear generation has far fewer emissions than natural gas, but most U.S. nuclear plants were built between 1970 and 1990 and their longevity is questionable. Regarding the future of natural gas, a report from the U.S. EPA’s National Renewable Energy Laboratory (NREL) about natural gas concluded:
“For the scenarios considered here [no, medium and high CO2 reduction levels], natural gas is an important player in the U.S. electricity sector out to 2050 regardless of the level of carbon reduction considered, though the role of natural gas varies based on the stringency of the carbon target imposed.
Natural gas [generation] on the [electrical] system may help to reduce curtailment of variable renewable energy resources. Under more stringent carbon mitigation, additional renewable energies are deployed, and the flexibility offered by natural gas offers least cost system wide solutions.” Source: Considering the Role of Natural Gas in the Deep Decarbonization of the U.S. Electricity Sector
A rough translation of this techno-speak is that natural gas will play a critical role in electricity production to 2050 and beyond regardless the renewable resource and decarbonization goals. It also says natural gas is expected to keep electricity costs low while enabling the increased use of renewable energy resources and the accelerating decarbonization.
The Case for Safer Cities Using Natural Gas DG
Natural gas Distributed Generation is commonly applied in the form of Combined Heat & Power (CHP) systems that replace conventional steam and hot water boilers in larger buildings. Unlike large utility-scale power plants burning natural gas, CHP systems capture the heat produced during the generation of electricity and utilize that heat to make steam or hot water or to power other equipment such as water chillers. Using this captured heat raises CHP energy efficiencies by up to 45% and reduces emissions by up to 30% compared to typical utility plants.
Following are some of reasons why natural gas DG, particularly CHP, is today’s intelligent compromise for safer cities. A natural gas CHP system installed in a large urban building:
- Increases the electrical security, reliability and resiliency of the building and the city
- Helps protect critical infrastructure from long outages
- Eliminates power quality problems
- Can operate independently from the electrical grid (a.k.a. “islanded”)
- Can start up without power from the grid (“blackstart”)
- Utilizes the inherently reliable natural gas system
- Aids in the increased use of renewable energy resources
- Reduces greenhouse gas emissions
- Can be developed into microgrids and mini-district heating systems for multiple buildings
- Reduces reliance and stress on the electrical grid
Your Natural Gas DG System
A natural gas DG system is a dedicated, premium electricity source for buildings nearly everywhere. The protection against blackouts provide a benefit in urban areas that can’t be matched by renewable resources.
Regardless location, the choices for natural gas CHP prime movers such as fuel cells, microturbines, combustion engines and gas turbines offer a range of different benefits. There are also many ways to optimize the use of captured waste heat.
The professionals at ENGIE MEP can help you design the natural gas DG system that’s right for your facility and your location. Whether you are looking for a simple replacement of a central plant to an electrical microgrid and mini-district heating system, ENGIE MEP has extensive experience delivering DG projects even in challenging urban situations where operations can’t be interrupted.