The financial, resilience, and sustainability impact will be different for each microgrid. An initial feasibility assessment by a qualified team will uncover the benefits and challenges you can expect from your system.
Early in the process, the “30% system design” phase may begin — often completed during the feasibility assessment. This lays out the basic technology types, sizes, locations, and methods of interconnecting the microgrid systems.
Ultimately, an accurate project cost estimate drives the feasibility, anticipated benefits, equipment bidding, and budgeting for system operation. This stage — which focuses on cost estimation and financial planning — also helps you determine who pays for the system. Internal financing allows you to take full advantage of the economic benefits, but third-party financing may be preferable if capital dollars are scarce or if state regulations do not allow utilities to own generation assets.
Next, going from a 30% design to fully fleshed-out blueprints with an interconnection agreement requires a high level of microgrid design expertise and familiarity with distribution equipment, much of which focuses on system engineering and utility interconnection.
When the construction phase begins and you will need to procure equipment, consider operating and life cycle costs over first cost, and don’t wait to order large pieces that have long lead times.
The actual installation requires local know-how and experience working in electrified environments. Pay attention to how and when equipment installation will affect your operations.
Next up, the system commissioning phase involves factory acceptance testing, site acceptance testing, and system commissioning. Again, consider when commissioning will affect your operations and customers. Training is also part of the commissioning process – comprehensive teaching on your microgrid’s features, functions, and operation.
Last, keeping a microgrid operating at optimal performance requires more than regular maintenance. A controller built specifically for microgrids can leverage weather forecasts and pricing signals, as well as system performance data, to continually optimize your microgrid. Having a well-trained operations staff (or contracting with a qualified third party) is critical.
Safety: The nature of microgrid topology generally means power can now flow in multiple directions. This means you may need to establish some enhanced safety practices — or at the very least, raise awareness of the risks associated with distributed generation.
Control: There are multiple facets to controlling your microgrid and planning for contingencies. You should know who specifically is in control of your microgrid and whether you can trust your microgrid controller. If the main control box or access to the Internet goes down, what happens to your microgrid? Can you only run in grid-tied mode? Will all generation assets simply run in their previous state until taken offline? Do you need to manually control devices to keep your system stable? Work through scenarios like these until you’re confident in your answers.
Cost: Controlling your microgrid’s costs starts during design. If assets are over- or under-sized because of mistakes introduced during engineering, you are either overpaying now (oversized) or underpaying now, but paying much more to fix the mistakes later (undersized).
Electrical stability: Ensuring your microgrid works means you need to verify all use cases in both steady-state scenarios and when load and generation aren’t balanced. This includes fringe cases (e.g., faults on the system, drops in large loads, drops in generation, starting up the grid from an unenergized state), which may only happen occasionally, but the grid must work through them — or at least recover from them. Sizing assets by using a simple spreadsheet to match generation to load isn’t sufficient to think through all use cases and scenarios.
Fully understand the components involved, including existing assets, hardware, integration services, controls and deployment services.
The report also discredits the following myths about building a microgrid:
- If I understand utility systems or the components of a microgrid (e.g., solar PV, energy storage, or generators), I understand microgrids
- All microgrids are the same
- Microgrids are so complicated, they make your problems worse
- Seamless transfer is necessary
- The more a microgrid can do, the better it will be
- Energy storage is required to run a microgrid
But even if you have defined some of your microgrid needs, it can be easy to overlook the details. Missing these details can result in increased costs and project delays. After deciding on the design of your microgrid, you also have to study the compliance regulations associated with creating a microgrid in your area or industry.
These include legislation like 1547-2018 – IEEE Standard for Interconnecting Distributed Resources with Electric Power Systems; P2030.7 – IEEE Draft Standard for the Specification of
Microgrid Controllers; Clean Air Act from the US Congress & the US Environmental Protection Agency, and more.
To explore building a microgrid further, the new report from S&C Electric covers the following integral steps and keys to success:
- Understanding Your Microgrid Lifecycle
- Approaching Microgrid Planning through Four Lenses
- The Components of a MIcrogrid
- Microgrid Element Connections
- Microgrid Myths
- Self-Assessment: Are You Ready for a Microgrid?
- Compliances You Need to Know About
- What to Look for in Equipment
- Why is the Microgrid Controller so Important?
- There’s More to Security than a Firewall
- Questions to Ask Your Microgrid Controls Provider
- What to Do if You’re Over Budget
- Integrator Evaluation Chart
- Relationship Advice: Working with Your Integrator
Learning more about building a microgrid. Stay tuned for the last article in this series.
- Choosing a Microgrid: A Modern Approach to Energy Challenges
- The Short- and Long-Term Care of Your Microgrid