Navigant Research Blog

Defining the New Smart Grid: From Nanogrids to Virtual Power Plants

— July 7, 2014

Nanogrids and microgrids are building blocks that, like Legos, can be stacked into modular structures: in this case, distribution networks that tailor energy services to the precise needs of end-users.  This customization of energy services is clearly the wave of the future; but determining where to draw the line between these two business models can be challenging.

In many ways, nanogrids are just small microgrids that typically serve a single load or building.  They thereby represent a less complex way to manage on-site distributed energy resources (DER).  Ideally, microgrids would be able to serve entire communities, but utility regulations often stand in the way.  These same regulations make nanogrids larger business opportunity today than microgrids, despite their smaller size.

The series of storms and extreme weather that have attacked East Coast grids in recent years has sparked interest in community resiliency initiatives.  New York’s Reform the Energy Vision (REV) initiative is designed to explore how multi-stakeholder community microgrids might provide emergency power to end-users ranging from a private gas station to a municipal fire station (and perhaps a community center emergency shelter).  Connecticut has been struggling with this issue of how best to include both public and private sector end-users, bumping up against the long-standing prohibition of transferring power among non-utilities over public rights-of-way.  To date, only one of the 9 projects approved for funding under Connecticut’s DEEP program is actually up and running, at Wesleyan University.

The Virtual Option

The third smart grid business model that can help build resiliency into power grids is described in Navigant Research’s report, Virtual Power Plants.  A virtual power plant (VPP) is a platform that shares many attributes with the microgrid (and the nanogrid).  In North America, the most common resources integrated into VPPs are demand response systems.  Though VPPs cannot guard against power outages at the customer site, they can play a key role in lowering overall demand on the larger utility grid, thereby stretching scarce resources, directing them to mission critical loads.

The lexicon of organizing structures required to handle the increasing complexity of energy supply and demand is growing.  In order to make sense of this brave, new world in energy, Navigant Research has come up with the following chart highlighting key attributes of three different business models.

 Comparing Nanogrids, Microgrids, and VPPS

(Source: Navigant Research)

Regulators clearly need to revisit regulations standing in the way of community microgrids.  It appears that New York is pioneering this debate, allowing it to surpass California’s position as the leading microgrid market in the country in terms of sheer numbers of projects in the works.  Moving downstream again, it is also important to remember that nanogrids help create smart buildings that, in turn, can also be integrated into VPPs.  These combinations are vital to efforts to harness greater value from DER, thereby increasing energy security.

In the end, it’s not nanogrids, or microgrids, or VPPs, but the deployment of all three in flexible and dynamic configurations that is revolutionizing what was once the staid world of top-down, command-and-control monopoly utilities.

 

Big Savings from Replacing Diesel with Storage

— July 6, 2014

In my previous blog on diesel and energy storage, I discussed the payback period for energy storage in a remote microgrid.  What is the value of reducing diesel usage in a microgrid, practically speaking?

The table below illustrates the first-year savings of displacing 15% of the diesel generation in microgrids of different sizes using energy storage.  The average installed energy storage cost in this model is $2,112 per kW, and the assumption for the minimum cost of diesel fuel is $1.09 per liter, with the maximum cost in the model averaging $3.27 per liter.  Since the installation of storage is a one-time cost that occurs in the first year, the savings go up after that.

Size Distribution of Deployed Microgrids and First-Year Fuel Savings
at Low and High Diesel Costs: 4Q 2013

ESMG table

(Source: Navigant Research)

According to Navigant Research’s Microgrid Deployment Tracker 2Q14, 231 deployed microgrids have diesel generation capacity.  This means that 38% of microgrids have diesel gensets, and overall, gensets account for 11% of microgrid capacity globally.  Only 40% of the 79 microgrids above 10 MW include diesel generators, and smaller systems are less likely to have diesel generation.  Less than one-third of the microgrids below 500 kW rely at least partially on diesel.

Taking the example of a large microgrid system, because this is where the savings are the greatest, microgrids over 10 MW average 42.7 MW of capacity.

Still Too Costly

Assuming a microgrid does in fact have diesel generation, if a 42 MW microgrid replaced 15% of its total capacity (and assuming at least 15% of that capacity would be displacing diesel gensets) with storage, it could save between $10.9 million and $53.4 million per year after storage costs are recouped.  The total savings for all of the large microgrid systems in Navigant Research’s Microgrid Deployment Tracker would amount to $2.2 billion to $10.8 billion per year in diesel fuel using just 200 MW of energy storage.

So why is storage not more popular in remote microgrids?  Chances are it’s because $2,112 per kW installed is still not competitive in most markets where storage is displacing traditional power generation – even with the benefits of volume manufacturing.  Companies such as Samsung SDI and LG Chem are manufacturing lithium ion cells for the grid at great volume, but it’s still challenging to deliver competitive prices to the customer.  This is because a large portion of costs has nothing to do with the core technology, and instead is related to project management, system design and integration, and installation.  As more companies such as Bosch and Schneider Electric enter the market and bring power electronics and energy management expertise to the storage space, these costs will come down significantly, benefiting the entire supply chain. 

 

Energy Storage Reduces Diesel Use in Microgrids

— June 6, 2014

One of the challenges to deploying energy storage in existing grids is building a convincing business case.  If the business case for storage is built on reducing or optimizing the use of diesel fuel, it doesn’t take much to get a positive return on investment (ROI) for a storage asset.  Two examples of diesel reduction applications are remote microgrids and mobile base stations.  In this blog, I’ll look at the numbers on remote microgrids.

Even using conservative assumptions, storage makes sense to rein in the total cost of ownership of remote power generation – and hopefully make operating systems, such as remote microgrids, less vulnerable to volatility in diesel prices.  For example, Ontario Power Authority has estimated that it spends CAD$68 million each year on diesel fuel for 20 remote communities.

Payback Time

In the case of remote microgrids, the storage system typically provides several benefits: diesel reduction, higher renewables penetration, and improved power quality.  Even if the business case is based only on diesel reduction, though, the ROI is still positive in less than 4 years across all advanced battery chemistries.  The forecasts in the chart below assume the replacement of all batteries except flow batteries at the 7-year mark – which may or may not be required.  It also assumes that for each kilowatt-hour (kWh) of energy, a diesel generator requires 0.3 liters of diesel, and that the cost of diesel is about $1 per liter and remains steady over the forecast period.

Less than 4 years is an impressive payback period, but the payback period is even shorter with a 25% increase in diesel prices. If the cost of diesel is $1.36 per liter, the payback period goes down to less than 3 years for all storage technologies.  At $1.64 per liter, the payback period shrinks to 2 years or less.

Cumulative Net Present Value of Energy Storage Technologies Integrated in Remote Microgrids by Battery Type, World Markets: 2013-2023

(Source: Navigant Research)

 

Enabling Remote Microgrids in the Developing World

— April 4, 2014

In my last blog, I wrote about the success mobile network operators (MNOs) are having with electrifying rural communities in developing regions, such as Latin America and Africa, by partnering with companies that sell solar home systems.  Much credit must go to the pico systems themselves, which are a cheap and reliable way to provide for the customer’s basic energy needs (cell phone charging and lighting).  However, there are two greater forces at play that reach far beyond the business of rural electrification: MNOs have found an effective business model in pay-as-you-go (PAYG) and they have employed an effective money transfer technology, known as mobile money.

These two forces answer the question: What has enabled the exponential growth of cell phone usage in the developing world?

Phone Bank

PAYG is a prepaid mobile phone plan.  You pay for a phone with a certain amount of airtime on it and you refill the time in your account as needed.  There’s no contract or monthly rate.  If you run out of time, your service is cut off, plain and simple.  This model works well for the off-grid rural poor who live on an inconsistent daily budget and who typically don’t have bank accounts.  It should be noted that some utilities in developed parts of the world are also experimenting with PAYG meters and they are finding that it is the only model that has successfully led to a change in consumer behavior (in the form of energy conservation).  As my colleague Peter Asmus details in his recent blog, this isn’t the only example of how the developed world can learn about energy solutions from the developing world.

Returning to the unbanked poor of the developing world, MNOs spotted an opportunity to capitalize on the lack of banking infrastructure in remote communities, and they have leveraged vendor networks and mobile technology to offer basic banking services to their customers.  To purchase airtime in the developing world, customers visit their local mobile airtime vendor and pay cash upfront for a scratch card of a certain value.  They enter the code from the scratch card into their phone to redeem the value of the card as mobile money, which goes directly into the mobile money wallet in their phone.  The mobile money wallet is protected by a PIN and acts essentially like a debit account, which can be used to purchase more airtime, along with other goods and services, to send and receive money, and to pay bills.  The MNO charges the customer for transactions made, so it is a lucrative new revenue stream for them.  More significantly for nanogrids, mobile money has opened the door to provide financing to unbanked customers.

Nanogrid Frontiers

Historically, one of the greatest barriers to off-grid households purchasing solar arrays has been the high upfront cost.  Investors, whether they’re vendors, microlenders, or nongovernmental organizations (NGOs), have had a hard time offering PAYG lending schemes to consumers due to the difficulty of collecting a long stream of small payments from a remote village, as well as the inability to monitor the systems.  Mobile money can provide a platform that enables lenders to conveniently offer PAYG schemes to off-grid consumers for the purchase of nanogrids, among other things.  More importantly, mobile money could turn remote parts of the world into profitable frontiers for the nanogrid market.  Many residential solar vendors (such as Simpa Networks in India) already see them that way, and these vendors are finding investors to finance PAYG systems as well as partners to handle the mobile money transactions.

While there is some variability in what these PAYG schemes look like, the keys to success seems to be the ability to track payments and usage easily and the ability to cut off service if a customer falls behind.  To view a list of nanogrid PAYG case studies, check out Navigant Research’s report, Nanogrids, and to learn about other business models that are being used to electrify remote parts of the world, view the replay of our Remote Microgrid Business Models webinar.

 

Blog Articles

Most Recent

By Date

Tags

Clean Transportation, Electric Vehicles, Policy & Regulation, Renewable Energy, Smart Energy Practice, Smart Energy Program, Smart Grid Practice, Smart Transportation Practice, Smart Transportation Program, Utility Innovations

By Author


{"userID":"","pageName":"Microgrids","path":"\/tag\/microgrids?page=2","date":"10\/25\/2014"}