1

Remote Power Units for Off-Grid Lighting and Urban Resilience

Patrick Burgess, Mohammad Shahidehpour, Mehdi Ganji, Dan Connors

Abstract

Currently, 18% of the world’s population (i.e., 1.2 Billion people) live without any access to electricity, referred to as energy poverty [1]. Many of these people burn kerosene or biomass as a source of light in simple lanterns, which unfortunately produces a devastating health effect that is equated to inhaling as much smoke as someone smoking two packs of cigarettes a day [2]. The off-grid Remote Power Unit (RPU) can provide continuous illumination for safer streets and safer driving that is unaffected by power outages. Due to individual lighting control potentially allowing for dimming, blinking, and even color changing, streetlights powered by RPUs can be used as emergency signaling devices, directing traffic during a city evacuation or other emergency. The RPU control and monitoring can be accessed through the cloud, which does not rely on local servers. The RPU and its communication network between units is self-powered, each light is individually controllable but can also be set to work in seamless conjunction with the other units. This way, street operators could potentially close off certain streets with red lights, direct vehicle traffic with synchronized dimming or blinking similar to airport runways, and signal to first responders, pedestrians, or vehicles of important areas such as emergency medical, supply, or evacuation stations or areas to avoid.

1. Introduction While the off-grid products create a new category of technology applications, the biggest challenge to their adoption will be to prove their technical worth and verify reasonable payback periods. Most places in the United States have access to an electric grid to plug in LED light fixtures, with the vast majority of cities already having path lighting and infrastructure on public streets. In such cases, the cost of an off-grid light with all of its features will likely be higher than that of a grid-tied LED light. There is a potential to make up this cost difference with increased revenue, however, without being grid tied to sell back extra renewable power to the grid, the payback on a swap from grid-tied high pressure sodium (HPS) street lights to the off-grid Remote Power Unit (RPU) is mainly based on cost savings from the high efficiency LED light fixture.

This swap in grid-connected cases may not immediately make financial sense, except in situations where there is not electrical infrastructure and installing hundreds of feet of conduit and running cable can be avoided by going with the off-grid solution, where sensor network or communication services are needed, or by grouping multiple RPUs with one point of interconnection. The added benefit in such cases is that if the grid loses power for any reason the lights remain illuminated indefinitely and can even provide a source of power for cellphones or other electronic devices. These power hubs can even be configured to power emergency communication equipment or similar devices if there is a severe emergency and resources such as diesel are in short supply, serving a real benefit to the community in terms of resilience.

Adding a community LED light fixture, powered by solar and wind units, to areas considered to be suffering from energy poverty would not only provide safety and security during the night, but could provide a spot for children to study without having to breathe in smoke from harmful kerosene [3]. The community light could also provide a community gathering spot for after dark meetings, conversations, celebrations, and more that are free from the harmful byproducts of burning kerosene or biomass for light and might not have been practical or even considered before an off-grid light was installed. In addition, an off-grid light

2

could provide free, local cellphone charging capabilities that rural residents, currently without access to electricity, may need to travel and pay high charging fees to accomplish. High initial costs can be offset with small loans shared among the community that reduce the amount of money that residents already pay for daily kerosene or cellphone charging.

There is also a potential to group such technology into grid tied configuration to overcome the high cost of interconnection of one of the units. The grid-tied option would require RPUs to be near an existing electric grid. For example, existing conventional light poles could be replaced by the grid-tied RPU using an approved micro-inverter. As the grid-tied RPU batteries can be charged during low cost, off-peak hours to supplement the wind/solar production, grid tied RPUs could reduce the requirement for sites with perfect weather conditions for wind and solar generation.

Figure 1 NY City and Dark Lower Manhattan in the aftermath of the 2012 blackout

At the end of the day, streetlights are installed for safety. Having an RPU located in the neighborhood depicted in Figure 1 that can provide the benefits of a regular streetlight, potentially add new revenue streams and less reliance on fossil fuels, and most importantly, provide a near 100% on-time operation even in the worst of situations, is a truly great thing in smart cities. Having a city plunged into total darkness causes residents fear, criminals to be emboldened, and the police, fire, and city managers a myriad of social and financial problems to solve. In Figure , having even one light shining in the aftermath of the New York blackout in 2012, would serve as a beacon of hope and provide incalculable benefits in terms of safety,

3

productivity, and peace of mind. The possibility of having city streets illuminated in such harrowing situations is not something to dismiss without serious consideration.

2. Off-Grid Lighting RPUs, such as the one manufactured by Aris, open doors to a myriad of on and off-grid applications not available with a standard street light. Figure shows the schematic drawing of an RPU, manufactured by Aris Corporation, with a 30 ft light pole and an LED light fixture that can withstand severe wind gusts. This specific unit has an access panel at 5 feet off the ground, which has a tool-required entry to prevent the average person walking by from stealing anything, damaging the unit, or hurting themselves. The unit has a wind turbine, with tail and duct, that reaches to a height of 29’ 7” and a powder coated white steel pole supporting it. The unit has a solar panel at a height of 19’ 3” and LED light with 8’ 2” supporting arm. It is also possible to have two solar panels and two LED lights on one pole.

Figure 2 RPU Dimensions

The RPU has an onboard monocrystalline solar panel, installed to face south with the least shading possible, a unique wind turbine that includes a fin help it turn and follow the wind as well as a duct-augmented wind turbine (DAWT) system [4]. This duct enhances the airflow into the blades at lower wind speeds, causing the generator to operate more often and produce more energy while also speeding up the startup time of the generator. This faster start allows for more consistent battery charging and powering of the LED lighting load. It is this feature that enables a smaller capacity turbine at only 30 feet high to consistently produce power, alleviating most of the concerns when relying solely on intermittent generation sources. In addition

4

to the generation, the unit encompasses a battery storage unit large enough to power the LED light for up to five days with no generation. This over-engineering was by design, and allows for the addition of a range of sensors, devices, or potentially for grid supporting services if the RPU is grid connected. The off-grid streetlights were also installed with USB charging station ports and pockets to allow for cellphone and other device charging as an example of the additional uses of the products, which include sensors, cameras, and supporting larger power needs when grouped together such as EV charging, emergency power, and more.

This advanced innovation uses fluid mechanics based technology for the RPU has the potential to invigorate the small and medium distributed wind generation market, illuminate and power remote areas, and revolutionize the sensor network and internet of things capabilities of cities. A combination of the deployed technology could provide true societal benefits in terms of reduction in electricity consumption and grid reliance, security and safety, and an opportunity to harness untapped wind power when integrated in urban environments, microgrids, and off-grid locations. This combination of benefits in such cases pushes standard technology into the fast lane towards smart cities.

The RPU specifications are listed in Table 1, which are broken down by section. The table shows the rated power for the permanent magnet wind turbine is 300 W, the turbine is rated for 9 m/s or 20 mph, and the cut-in wind speed is 2 m/s or 4.5 mph. This low cut-in speed is largely due to the DAWT system, which can greatly increase the energy generated by each RPU.

In addition, the RPU includes one or two 250 W and rated solar panels that are standard 60 cell format and approximately 65” by 36” and the rated power output is lower than that of the wind turbine. By combining both wind and solar generation on a single unit, the RPU uses the 24-hour availability of wind to complement daytime solar. This could be beneficial in variable weather locations such as Chicago where there high winds with low sun for consecutive days and sunny days with low wind at other times.

Table 1 RPU Specifications

In Table 1, LED lights with one or two fixtures, depending on the location and wind and solar potential, can be installed with attachment arm at 60, 70, or 80 W rating, with 80 W being the standard. The 80W rated

5

LED is commonly used to replace 150W HPS fixtures. The control system section mentions an Airsynergy hybrid controller as the unit’s charge controller and more detail is provided in the controller section below. The batteries contained in the unit are two 12V absorbent glass mat (AGM) batteries that are connected in series to provide 24V storage. The batteries are available in 150, 200, 230 amp-hour (Ah) capacity options. The AGM battery contains fine fiberglass mats that absorb the sulfuric acid, making it spill proof and very resistant to vibrations [5]. The AGM has a long life, low maintenance, and is relatively reliable and light. The biggest downside is the high cost to manufacture [6]. The tower is made of galvanized steel that is powder coated a standard white, but can be optionally coated in green or brown.

3. RPU Applications

An LED light pole that integrates solar, wind, and battery energy storage, while taking up no additional real estate, is self-sustaining, can be used in an off-grid configuration, and can be remotely monitored and controlled is a valuable concept that, if leveraged correctly, could have an interesting future supporting the shift from fossil fuels to clean energy.

A different application of the RPU would be to connect it back to the electric grid and to use the excess solar and wind power to feed the grid load while also using the battery to support the grid through ancillary services, energy arbitrage, or backup power. One of biggest issues to market penetration of this solution will be the fact that the cost of interconnection to the local electric grid for a single RPU may outweigh the generation benefits from such a small unit. A solution would be to group say 10-20 units together on a single feeder and have one interconnection point with the utility to maximize the benefits while minimizing the overhead costs. An example of this application might be a large parking lot with 80 to 100 lights that can be replaced with RPUs and tied to the surrounding grid or microgrid at one or two points. This way you are adding as much as 55 kilowatts (kW) of generation and 23 kAh of battery capacity to your grid without taking up any additional space on the roof or in the basement of your building. This idea has yet to be tested and does face technical challenges, but could yield exciting results.

Illinois Institute of Technology (IIT) located in Chicago was considered as a prime test site due to its local smart grid network that is leveraged to implement advanced communications or sensors with the RPU fixtures [7]. IIT has a 200 LED street lighting installation as shown in Figure 3 3, which is used as a pilot and use case for local municipalities and for a City of Chicago lighting expansion [8].

Figure 3 IIT Pilot Before (Left) and After (Right)

6

The Aris RPU installation shown in Figure 4 lights the pathway across from the IIT’s athletic center and newly upgraded DC nanogrid that relies on rooftop solar, batteries, and LED lighting connected by a DC bus, Keating Hall. The Keating Hall front entrance was chosen due to its nightly reliance on limited building flood lighting, its normal hours of use going until at least 10 pm weekly, and the important fact that there was no existing underground wiring installed in the area in need of lighting. These RPUs can stay powered on for up to five days with a full charge and no solar or wind generation and are robust enough to handle even the varied weather conditions in Chicago.

Figure 4 Keating Aris RPUs at Dusk

4. Structure of RPU Controller

The installation at IIT provides an opportunity to demonstrate multiple units in operation cranking away silently during the day or brightly lighting the previously dark pathway at night. In addition to the intrinsic benefits, having four units with nearly the same weather and wind conditions and the ability to treat them as a shared resource allows for direct comparison of performance, rigorous benchmark testing, communication module piloting, multiple environmental sensors, security device and camera integration, and implementation of real time monitoring in existing asset management software in the microgrid.

A major aspect of the RPU that is critical to the successful operation and control of the unit is the on board controller that optimizes generation and schedules the light. This controller must take into account solar and wind generation, battery charging and discharging, and serving the lighting load. It also must decide what to do in times of over generation, under generation, high winds, temperature or other equipment malfunctions as well as interface with the communication module to provide real time and historical data and status flags and notifications. The standard communication that the RPU uses is relatively expensive as it uses an individual cellular chip and antenna to send data back to the controller interface, but it does work well in remote installations

The controller interface, shown in Figure 5 , allows users to access individual units through the Ethernet. The user is able to see real-time data points, including battery voltage in Volts (V), total charge in amp

7

hours (Ah) and kilowatt hours (kWh), wind generator voltage, current in amps (A), power output in Watts (W), speed in rotations per minute (RPM), solar voltage, current, and power, as well as the LED lighting load information including on/off status, current, and total load energy in AH and kWh.

Figure 5 Aris Wind's RPU controller interface

The controller input is the float, charge off, and user on and off voltages of the battery, the longitude and

latitude and time zone for sunset and sunrise ramp up/down of the light in the date time section, the

maximum speed of the wind turbine blades, as well as the brake voltage and current, or the set point at

which the wind turbine will automatically brake to protect the unit, and charge mode. The wind section

allows the user to select the charge mode between the options hill climbing, U-I table, and Pulse Width

Modulation (PWM). The options can be used due to the intermittent nature of wind and solar resources,

the battery needs special care when charging under these situations to ensure efficient charging and

maximum life of the battery, however they have not been extensively tested by Aris. Hill climbing, or

maximum power point tracking (MPPT), increases efficiency of charging and allows the system to operate

at its maximum power point by continuously monitoring voltage and current and using these in the control

feedback loop with a DC/DC converter and MPPT algorithm [9].

The U-I table is the chosen method of charge for the wind turbine to charge the AGM batteries included in

the RPU. This method involves four stages of charge, bulk, absorption, equalization, and float, which can be

seen in U-I Mapping Data table in Figure 5 . The portion of the chart with a constant 20A between 105 and

8

190V is the bulk charging where up to 80% of the battery is charged. The portion between roughly 3A and

19A and 73V to 103V is the absorption phase where up to 95% of the battery is charged [10]. Equalization is

optional and is roughly the portion from 1A to 3A or 50V to 73V where the battery is topped off to near

100% using a true constant current method to speed up this normally time consuming portion. The final

portion of the charge cycle is the float, storage, or maintenance mode and voltage is kept nearly flat to

maintain the voltage until discharging

Constant voltage battery charging and higher charging efficiency can be obtained through PWM or slowly

decrementing the charging current when the battery hits it regulation setpoint while continuing to return

the maximum power [11]. The solar section input allows selection of the charge mode, and finally the load

section allows a max current, light switch voltage, delay, dimming mode, and a moderate level of

complexity of possible on/off and dimming schedules that can be set at arbitrary times as well as sunset

and sunrise. The record button allows you to select intervals from 1 second and up and records available

data to excel format for the duration that you are connected from when you hit record to when you stop.

The RPU controller was developed to optimize the two sources of renewable generation, the battery energy

storage charging and discharging, as well as the LED lighting load, through the charge control options listed

above and the other RPU controller inputs. This unique configuration is reminiscent of a microgrid master

controller due to the optimization and control it contains, but is lacking the need for grid communication

and coordination due to the units being off-grid. The possibility of similar lighting units being grid tied could

utilize adaptive weather conditions, day ahead scheduling, and ancillary service market interfacing aspects

to realize the full potential of grid tied consumer benefits. This could create nanogrid control and operation

situations when parking lots or facility lights are converted to grid tied units with solar, wind, batteries, and

LED lights and are used to power facility or building assets, if the controller is upgraded to provide these

benefits.

The RPU controller is designed to maximize service to the LED lighting load by optimally charging the

battery from all available wind and solar throughout the day. Due to favorable conditions in Chicago during

the summer, there are many days that the battery is fully charged by 10-11 am on an 8-5-8 dimming

schedule with the light coming on at 8 out of 10 brightness – 10 is fully bright and 0 is off – at sunset, dims

to 5 out of 10 brightness from midnight to 4:30 AM, and spends the remaining time until sunrise at 8 out of

10 brightness. The controller actually has a resistive circuit that it can send excess power to, to avoid

damage to the battery when there is excess generation. As the city approached the winter solstice, the RPU

units at IIT needed to be changed to a 5-3-5 dimming schedule to accommodate long nights with days of

gray and low wind conditions for days on end. The controller will also brake the wind turbine to prevent

over charging of the battery, in the event that there is excess generation. This performance supports the

proposal to utilize the RPUs as communication towers, sensor hubs, or for advanced grid tied and grid

support functions due to the extra power generated.

RPUs can be utilized as sensor hubs due to the ease of integrating physical sensors and the communications

backhaul as well as the ability to remotely power the sensors or devices [12]. The question of power was

proven at IIT in summer operation as the four RPUs regularly become fully charged together by the morning

and had additional power reserves throughout the day to charge cellphones or supply sensors and devices.

In winter operation, programmable dimming can balance lighting versus power generation and lighting

versus other loads. The RPUs have a 20-foot weather proofed tower rated at 120 MPH which can easily

house the large 230 Ah batteries in its base and provide ample space for any additional sensors and

associated controls or storage. The RPUs are also placed away from building and tree obstructions that

might interfere with solar and wind generation, leaving a structure that is perfectly suited for wireless

9

communications. The RPU controller has a simple, standard Ethernet interface, making it possible to add

functionality or integrate sensors for control and communication purposes.

5. RPU Testing at IIT

The four installed RPUs on IIT campus have been in operation since August of 2016. The IIT team has

periodically collected operating data that demonstrate the RPU’s operation and control dynamics, as well

as basic functionality. The ultimate test of an off-grid light is that the light stays on during evening hours

and that the hardware is functioning correctly.

Since the units were installed, the vast majority of the time the units were operating flawlessly with the

battery becoming fully charged between 9am and 11am and excess energy being generated throughout the

day. Figure 6 shows the data collected from an average 8-5-8 dimming schedule day with moderate cloudy

solar and consistent wind generation. The battery reaches peak voltage and float state around 9am in the

chart below. Even with non-ideal generation, the battery and LED lighting load performed well with excess

power to spare for cellphone charging, sensor networks, or other communication applications.

With minor variances due to changing weather conditions, the RPUs have performed similarly since startup,

with the only issues due to a delay in changing to winter settings too close to the winter solstice. Figures 7

and 8 show a two day operation of the IIT RPU in December. Figure shows the battery voltage (V) and the

LED lighting load (A) with the distinct 5-3-5 dimming pattern mentioned above. Here, as the lighting load is

served by the battery, the battery voltage gradually drops on the first day until the light goes off in the

morning; however, the battery voltage stays constant throughout the second night. This is due to the

nighttime wind depicted in Figure supporting a more consistent battery voltage and allowing for a faster

recharge of the battery in the morning, with the battery reaching its peak voltage around 9:30 AM instead

of 11:30 AM on the first full day shown.

Figure 6 Data Showing an Average Day of Operation of IITs Aris RPUs

10

Figure 7 Battery Voltage and LED Lighting Load in Amps of IIT RPU Installation in December

Figure 8 Solar and Wind Power and Battery Voltage of RPU Installation at IIT

It should also be noted that this data was taken during a period of non-ideal weather conditions shortly

after the settings where changed from 8-5-8 to 5-3-5 and that the LED light actually turned off in the

morning around 6 AM, when it was supposed to be on until about 7 AM, due to the falling voltage. This was

due to the battery reaching the user off voltage of 21V, and while one hour during dawn is relatively

11

insignificant, it is a sign to the operator that the settings need to be changed earlier in the year to ensure a

100% successful operation. This condition is due to the fact that the generation in a day may have a slight

deficit that adds up in consecutive days as the battery reaches a slightly lower capacity peak every day. This

condition can be solved with a learning algorithm applied to the controller that can automatically adjust the

settings based on generation profiles.

An example of an RPU that does not have the same variability and long winters of Chicago is shown in

Figure . This location is one the highest performing RPUs for the Aris wind unit. It can be seen that the LED

light is operating on a 10-10-10 dimming schedule, or maximum brightness for the whole night, and the

battery voltage hovers around 25 V with a variance of only 2V from night until day. The wind generation

peaks at 150W and shows a consistent night time generation which stops generating consistently for about

15 hours out of 58 hours recorded. The solar generation starts strong on both days and continues at over

200W generated until noon each day when it drops off until nearly zero for three hours and only picks back

up for the tail end of the solar day due to shading from an unfortunately positioned utility pole that creates

shade on the RPU solar panel.

Figure 9 RPU Installed at another Location with Ideal Weather Conditions

An exciting aspect of having four RPUs in one location is the comparison of the four units for a more

accurate benchmark of performance. Figure shows a comparison of the energy charged by the battery and

discharged by the LED lighting load of the four RPUs at the IIT campus which all perform relatively similarly

with no one light standing out as a low or high performer. This indicates that the wind and solar conditions

are nearly similar and that the RPUs are responding similarly to wind obstruction from nearby buildings and

12

from any shading of the solar panels caused by nearby obstructions. The difference between battery energy

(blue) and lighting energy (orange) is due to nighttime wind.

6. RPU Communication Integration

While the existing communication makes sense when RPUs are installed individually in relatively remote

areas, an installation of multiple RPUs in an urban area with the existing smart grid communication

networks can benefit from tapping into this existing generation resource for lowering costs and improving

RPU functionality. Resilience is provided through the mesh network capability by using a mesh network (like

Silver Spring’s radio system) to connect the fixtures and existing wireless neighborhood area network (NAN)

to wide area network (WAN) access points (APs). Accordingly, networked RPUs can form an information

highway that either strengthens the existing mesh or connects multiple networks or devices that are in

relatively remote areas.

The Starfish Network (provided by Silver Spring Networks) which is a worldwide wireless IPv6 network

service deployed at IIT for the Internet of Things, providing secure, reliable, and scalable connections to

devices and sensors using a wide variety of standards-based wired and wireless communication protocols.

Starfish enables commercial enterprises, cities, utilities, and developers to access the vast amounts of new

data being created by these intelligent endpoints and to create insights from these data that improve

efficiencies and quality of life. Using Starfish, cities around the globe can leverage to connect intelligent

devices and sensors to address water, energy, food, traffic, transportation and safety issues that impact

everyday life. The Starfish Network considers projects that include IIT campus streetlights, water meters,

and other smart city infrastructure.

Figure 10 Energy Charged by the Battery and Discharged by the LED Lighting Load at IIT

RPUs can act as vital nodes in these communication pathways by powering wireless mesh radios in even the

remotest of areas that don’t have the power for conventional communications. Companies are investing in

13

pay as you go plans to solve the problem of rural and remote electrification in India, South America, the

Middle East, and Southeast Asia. This model allows a company to invest in a solar and battery installation in

remote areas and for residents to buy units of electricity through their phones, buying power as they need

it instead of on a contract. The challenge with this model is that cellular communications on each small

solar installation in many small villages is expensive and not completely reliable. This hurts their ability to

provide reliable power, to monitor the units’ performance, and to receive notifications when the units need

maintenance, making system management a nightmare.

A possible solution arises when one considers the possibility of adding wirelessly controlled lights along

major highways coming from cities where the power companies are based and traveling nearby the

remotest of towns [13]. The mesh network formed by this information highway would allow for a

community of RPUs to act as the access point for control and operation of the villages solar installation. This

is because many towns are nearby to highways and even the remotest villages can be configured to ‘hop’

back to the main highway as standard smart grid 900 MHz radio signals can travel over a mile in good

conditions. This solution allows developing countries to leapfrog the rest of the world for arriving at an

efficient distributed generation solution, see Figure 1 for an example of the large difference lighting can

make in a small village.

Figure 1 Village Streetlight

14

7. RPU as a Sensor Hub Considering the integrated network interface device, we can utilize RPUs as hubs for measurement sensors

and as communication highways. Sensors would be able to collect data on various conditions like weather,

environment, and safety and utilize the communication network to securely transmit these data back to

operators for analyses. For example, companies could install environmental sensors for conditions such as

temperature of the roadway or ground to determine if streets are approaching icy conditions before salt

trucks are dispatched, to prevent danger to drivers and optimize salting at areas where it is needed most.

Environmental sensors will track myriad pollutant and air quality levels over time and provide the remote

data without fully developed electrical infrastructure. The data could be extremely valuable for managing

the conditions in remote areas. RPUs could also be equipped with security cameras, motion sensors,

gunshot detectors, or similar situational awareness sensors that could inform law enforcement personnel

or security services of threats or changing conditions. Figure 2 depicts a representation of communication

between different light poles and the opening of a network of potential applications for wireless sensors.

Note that all the other RPU attributes still apply, including the kWh energy usage reduction, 100%

renewable and resilient power, public service features and end user sustainability branding/message.

Figure 2 Wireless Sensor Network

While one RPU is not able to produce enough electric current to power even a level 1 charger, depending

on wind and solar potential, an integrated EV charger can be powered by as many as five nearby RPUs. This

would allow parking lots to install EV chargers without adding in the expensive additional electrical

infrastructure required, just with a streetlight upgrade. The controller is already designed to manage load,

but changes would have to be made to ensure that the batteries of each individual unit will have enough

charge to power the LED lights for the entire night as well as charge EVs during the day, however it is

possible with enough RPUs to have as much generation and storage as is required. In addition, the

controllers would have to work together, which is not something they are currently programmed to do. This

15

would be relatively easy using Silver Spring radios for communication, as they would all be on the same

local mesh network [14].

8. RPUs in Smart Cities

As we consider the future of metropolitan cities across the globe and take into account the accelerating

migration of people into large cities in pursuit of better living conditions, we recognize that we will soon be

faced with real challenges to provide food, water, living space, energy, and security to growing city

populations. There is a nexus between these major commodities, as shown in Figure 3 which is developed

by Willdan Energy Solutions, that requires careful planning and implementation of cities as they grow in

order to ensure all needs are being met concurrently. We cannot have clean abundant water without

energy resources, food production relies heavily on water for growth and energy is a necessity for keeping

lights on, houses warm, and transportation system intact, and energy, water, and food require secure and

safe cities for operation. A robust and resilient communication network will be the backbone of the future

cities. Every aspect discussed around the nexus will require intelligent devices that monitor and control

every aspect, generate massive amounts of data, and inform operators and users of changing situations.

These devices will be connected in an array of different networks that utilize different frequencies and

protocols in many cases will have to interface with each other to successful manage and operate the

system.

This enigma of a system of networks will also have to maintain confidential and sensitive information with

the utmost care and secrecy and prevent unauthorized users from accessing or manipulating the data. This

cyber security question is one of the most pressing issues of our time and can lead us into an era of no true

privacy and authoritarian control as states and non-state elements wage cyber warfare, or, more likely, into

an age where the cyber physical becomes more important and we use our unique body signatures as

passwords or carry digital implants to maintain secure systems.

Figure 3 Smart Cities

16

9. Conclusion The potential offered by off-grid lights will be applied in developing countries or integrated into established

grids and urban infrastructure, launching smart cities that can reduce congestion, pollution, and crime.

Utilizing small and agile products such as RPUs and advancing their designed use through innovation and

practical interface with other nexus items will enhance our opportunity to be part of the shift into smart

cities and grow a variety of connections among smart cities solutions. Off grid lighting can serve as hopeful

energy hubs for village residents to charge devices and cellphones, power community support systems,

serve as after dark meeting locations, educational or studying locations, and provide safe passages for

nighttime peddlers. These changes embedded into smart cities can provide a source of electricity for those

who live without it and remove the need to burn oil lamps, refuse, and cow chips for light and cooking,

improving air quality and health. Urban off-grid lighting can be leveraged by educational and research hubs

to connect utility, industry, government, and academia in partnerships that support students, industry

communication and smart grid application companies, and city management departments. All of these

applications benefit consumers and other end users from a much more efficient concept to implementation

timeline.

In both rural and urban environments, smart lighting and city-wide smart grid communication networks

integrated in such light poles enable a myriad of smart city applications that are beneficial to society. The

possibility of enabling distributed, pay as you go, renewable generation-based electricity access for villagers

who currently have no access to electricity and travel many miles to pay half-a-day’s wages to charge their

cellphone, and the chance of reducing harmful emissions or slowing global climate change effects are all

worth the investment in RPU technology. The possibility of having normal grid condition benefits of

reducing emissions and traffic, increasing the efficiency of snow removal and the safety of nearly frozen

streets, protection of law enforcement, and faster reactions of first responders also promote the

investment in RPU technology. Even more importantly, the possibility of having an operational grid in

emergency conditions, maintaining street and traffic lights during city blackouts, as well as enabling

emergency communications among government and city managers, emergency personnel, and first

responders, are worth an investment in RPU technology.

The biggest resource we possess to make major social changes is the current and future generation of

engineers, scientists, and lawmakers who will continue taking up the mantle to address and aggressively

work to slow down climate changes, invest manpower in enhancing the cyber security for our major

infrastructure, reduce reliance on fossil fuels, be more conscious of our water use and of the quickly

growing problem of fresh water scarcity, and move to more sustainable practices in agriculture, food,

construction, and manufacturing. It is also our responsibility to be the change we want to see embedded in

smart cities throughout our planet.

References 1. “Empowering the Global Poor,” Energy Times, http://iitmicrogrid.net/gallery.aspx#prettyPhoto/37/. 2. http://www.who.int/indoorair/publications/fflsection1.pdf

3. http://www.iea.org/newsroom/news/2014/march/when-measuring-energy-poverty-the-best-and-latest-data-come-from-the-iea.html

4. Connors, Dan, "Wind Products." Aris Wind Comments. Aris Wind, n.d. Web. 04 Nov. 2016.

5. https://www.solar-electric.com/agm-battery-technology.html 6. http://batteryuniversity.com/learn/article/absorbent_glass_mat_agm

17

7. W. Archibald, Z. Li, M. Shahidehpour, S. Johanns, and T. Levitsky, “Islands in the Sun: The Solar Power Deployment Initiative at the University of the Virgin Islands,” IEEE Electrification Magazine, Vol. 3, No. 1, pp. 56-67, Mar. 2015

8. “Struggling Chicago Community Transformed by New Energy Future,” Scientific America, http://iitmicrogrid.net/gallery.aspx#prettyPhoto/24/.

9. https://www.researchgate.net/publication/288128372_HILL_CLIMBING_TECHNIQUES_FOR_TRACKING_ MAXIMUM_POWER_POINT_IN_SOLAR_PHOTOVOLTAIC_SYSTEMS-A_REVIEW

10. https://www.nyc-arecs.org/charging.pdf 11. http://www.morningstarcorp.com/wp-content/uploads/2014/02/8.-Why-PWM1.pdf 12. Ahson, By, "Wireless Sensor Network Applications." TECH EXE. N.p., 03 Nov. 2016. Web. 04 Nov. 2016.

13. Verhaar, Harry, "Solar LED Brings 'leapfrog' Lighting to Off-grid India and Thailand - Cities Today -

Connecting the World's Urban Leaders," Cities Today. PFD Publications Ltd, 29 Feb. 2016. Web. 04 Nov.

2016.

14. M. Khodayar and M. Shahidehpour, “Cutting Campus Energy Costs with Hierarchical Control: The Economical and Reliable Operation of a Microgrid,” IEEE Electrification Magazine, Vol. 1, No. 1, pp. 40-56, Sept. 2013