Understanding the Definitions and Defining Microgrid

• Understanding the Definitions and

Defining Microgrid Language

• Deploying Microgrids

• Lessons Learned and Success Factors

• Additional Resources

Section 1 - Microgrid OBJECTIVES

What is a Microgrid?• Microgrids are defined by their function, not their size

• Independent Energy Systems

• Key components:

– Generation

– Control

– Distribution

– Storage

– Load

• All linked together in a network, they can operate as an

isolated mini-grid or interact with the utility

Image courtesy ZBBEnergy.com

Microgrid-enabling technologies

• Distributed Generation (DG)

• Islanding Inverters

• Smart Meters

• Distribution Automation (DA)

• Substation Automation

• Microgrid Control Systems

• Smart Transfer Switches

• Advanced Energy Storage

Securicon, LLC

Types of Microgrids

• Off-Grid Microgrid

• Campus Microgrids

• Community Microgrids

• Nanogrids/Picogrids

Kenya

Tanzania

Cape Verde

AC Coupled, DC Coupled and Hybrid

Solar Microgrid Configurations

University microgrid feasibility study in Ghana - 2015

AC Coupled

The storage inverter controls battery charging/discharging

Pros Cons

Improved conversion efficiencies Typically more expensive

Simplified serviceability and system

monitoringLarger physical space requirements

Easier to isolate the storage system

for troubleshooting

System control can be harder with

two inverters

AC Coupled

DC Coupled

Power flow from both the battery & utility ports

is bi-directional

Pros Cons

Can reduce material and labor costs Harder to find and source products

Generally more compact (Physical space) Lack of functionality

Simpler design & can provide performance

benefitsNo revenue grade meters available

DC Coupled

Hybrid

Integrates additional generator(s) – AC or DC coupled

Pros Cons

Reduces energy storage capacity

requirementsCost of Diesel or other fuel

Extended days of autonomy Generator Maintenance

Increase overall system reliability

and resiliency

Increased complexity = more

complex commissioning and

troubleshooting

Hybrid

Engineering/Design Considerations

• Energy Storage

• Site Evaluation

• Design Calculations

• Point of Connection

• Backup Loads

• Sequence of Operations

• Safety

EarthSpark Microgrid - 93kw PV in Haiti

System capabilities

– Stacking

– Control System

Microgrid distribution infrastructure in Les Anglais

Managing Customer Expectations

Economic performance

– Costs of operation

– Life expectancy of components (Batteries)

1st Technical Step in Deployment…

• Project screening and

Rapid Assessment

Sensitivity analysis helps point to where more data is

needed

Microgrid Engineering Optimization

• Calculates the total lifetime system cost

– Installation costs

– Operation and Maintenance costs

– Replacement costs and salvage value

Fits all the pieces together

Peter Lilienthal, Ph.D.

Additional Resources

Case Studies and Tools Mini Grid Policy Toolkit*

http://minigridpolicytoolkit.euei-pdf.org/downloads

http://minigridpolicytoolkit.euei-pdf.org/policy-toolkit

Resources

Sunny Island SMA Microgrid Video

http://microgridknowledge.com

http://www.microgridinstitute.org

• Overview of Haitian Context

• Discuss EarthSpark Model and History

• SparkMeter™ and Evolving Models

• Pre-Payment System and Tier system

• Challenges – Theft*

• Lessons Learned and Success Factors

Section 2 – EarthSpark Objectives

Haitian Context• In Haiti 75% of households lack access to electricity

• Households spend an

average of $10/month* on

kerosene and candles

and $4/month on cell

phone charging

* Approx. 6.5% of annual income on household lighting

Haiti’s National Electric Grid

• Owned by Electricitè d’Haiti (EDH)

– Poor infrastructure and maintenance

– Old and deteriorating equipment

– Power is primarily produced by diesel and HFO

generators

• Unstable network

– Outages are frequent and often unscheduled for the small

percentage of the population that has access to the

national grid

Haiti’s National Electric Grid

Between 2002-2003,Haiti suffered from a total loss

rate of 53.6%1 (Including technical and non-technical losses).

Theft of electricity is also a major problem in Haiti –

In 2002, approx. 64% of utility electricity produced

was unmetered!

Source: Ministry for Public Works, Transportation and Communications

Mission: to eradicate energy poverty

Method: R&D on business models that can

spin off and scale

EarthSpark International

Energy Access market segmentation by location

and consumption Central Grid

Grid Extension and Infill

Microgrids and captive storage

Stand-alone-systems

(small and large)

• Pre-Payment – Allows customers to purchase

electricity as they purchase kerosene – in small

quantities as needed.

• Deep Efficiency – Begins with locally available

appliance options

• Accompaniment – Value chain and clean energy

products

“Integrated Rural Electrification”*

“Building Clean Energy Access”

EarthSpark Model

Clean Energy Retail

Haitian Social Enterprise

• Small-scale Solar

• Portable Solar Lighting

• Efficient Cookstoves

With a national network of over 100 retailers

EARTHSPARK INTERNATIONAL

Haiti’s first prepay microgrid

‘The country’s only 24/7 source of

community electricity’

EARTHSPARK INTERNATIONAL

• 93 kW of PV

• 450 kWhs of Battery Capacity

• 30 kVA Diesel Backup

Microgrid Timeline – Stage 1

201214

CustomersPowered by Spare

Diesel Generator

Microgrid Timeline – Stage 2

201354

CustomersPowered by Spare

Diesel Generator

Microgrid Timeline – Stage 3

2015440

Customers

Powered by Solar PV,

Battery Bank and

backup Diesel

Generator

LOW Cost, HIGH Functionality

Smart Meter

SparkMeter™

• Pre-payment – Enables cost

recovery and payment

assurance

SparkMeter™ System

Consists of four major

components(under development)

• INDIA

– 150 households spread over several kilometers

• NEPAL

– 83 households, 25 micro-enterprises and 2 cell towers

(3 separate microgrids dozens of kilometers apart)

• TANZANIA

– Pilot microgrid by E.ON Off Grid Solutions with 20

current customers

• HAITI

– 440 customers on a single microgrid

http://energyaccess.org/news/recent-news/sparkmeter-brings-smart-grid-functionality-to-underserved-utility-customers/

Current SparkMeter™ Installations

SparkMeter™ Features

• Time-of-use pricing

• Load limiting

• Flat rate or block rate

• Monthly plan option

Tiered Load Limiting System

Anchor: > 600 W

Gwo Bagay: 600 W

Freezer: 360 W

TV: 120 W

Limye: 30 W

5 Levels

• 65% are using Limye

(light in Haitian Creole)

• ABC Model – Anchor, Business, Community

Time-of-use pricing

• The tariffs are based on time of day

• Large customers pay less per kWh

Approx. 34¢ - 60¢ per kWh (USA)

• Higher cost at night to incentivize customers

Additional Features…• Monthly Plan – defines

the minimum that a

customer must spend

• If customers don’t spend

the minimum they go

down a level…

• Load Limiting – The

operator can define a

limit between 2W and 4.8KW

• Non-Payment Shutoff

• Auto-shutoff when using

excess power(Allows for surge loads)

Anchor: > 600 W

Gwo Bagay: 600 W

Freezer: 360 W

TV: 120 W

Limye: 30 W

Solving Core Problems for Grid Utilities

Written by Allison Archambault

Overall Challenges • Dealing with theft

• Smart metering required

• Scarcity of specialized equipment

• Harsh environment for electronics

• Ensuring timely payments

• Lack of efficient appliances

• Lack of regulatory framework

• Lack of skilled technicians

Electricity Theft• Changing views on theft from…

• Community pressure

• Imposing fines

• Justice system

A way to ‘beat the system’

Stealing from the community

Electricity Theft• Lesson Learned Place multiple meters on tall poles

• Currently addressed by:

– Checking connection

at each house

• Future Strategy

– Use of Totalizer Meters

Lessons Learned

Supply is less than 1/2 of the equation!

– Need comprehensive load-driven analysis

– Demand doesn’t always match the supply

Storage and smart meters can smooth out peaks

in electrical demand

Thinking only about supply isn't enough, it’s about timing.

The Mill’s Electrical Electrical Requirements

The mill experiences extreme peaks in mornings

and especially on market days.

Prioritize energy services, not kWhs

Ice Making• Used to cool drinks

(coolers vs. refrigeration)

Breadfruit Processing• Harvested at same time and has

short shelf life

– Rots quickly if not processed

– Processing with electricity flour lasts

for months

Microgrid Success Factors

It is important to develop a comprehensive approach

to clean energy access

• Densely populated rural areas

– Smaller geographic area reduces time needed to

visit customers • Reduces electrical distribution costs

• Information can be easy communicated to the community

Microgrid Success Factors

• Multi-disciplinary planning and community

partnerships are KEY

– Begin by establishing an energy baseline

• Find out what people are currently using and how

much they are paying

• Desirability of pay-as-you-go

• Reliable revenue from larger customers with

PPAs and monthly billing plans

Accompanying opportunities

• Value Chain Synergies

• Fuel switching (cookstoves)

• Agriculture + Conservation

• Feminist Electrification

• Energy Efficiency Services• Sourcing energy efficient appliances

• Offering technical expertise

Virtuous Cycle

Productive businesses

strengthen the grid

The grid unlocks productive use

value

Electricity for community-based development!

Thank you

ALLISON ARCHAMBAULT

PRESIDENT

JAMIE TRAHAN

MICROGRID SPECIALIST