Solar PV for Water and Wastewater Systems

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1 Lonnie Russell, CEM, REP Solar PV for Water and Wastewater Systems Jasper County Florence SC

2 Why Solar in South Carolina? PV price is dropping Laws have improved Better for environment Cleaner Air brings a higher quality of life Energy Independence (both foreign and domestic) Fossil fuels are a limited resource, and all of them have pollutants (smog, acid rain etc..) Solar is the only renewable energy source capable of supplying 100% of the earth s energy needs. Traditional energy sources are getting more expensive South Carolina has lots of Sun! Can be distributed - power source closer to load bring benefits and efficiency to grid

3 Advantages/Disadvantages of Solar PV PRO No moving parts Not much maintenance required Solar PV systems are reliable, modular, durable and generally maintenance free. It can be located at the place of use and hence no distribution network is required. These systems are quiet, compatible with almost all environments, expected life span of 20 years or more (30 is more likely). PV is scalable CON Intermittent power, storage required if off grid needed Large number of panels required to generate substantial power Efficiency of panels is low Price has been prohibitive, though that is changing quickly

4 > 100 : Redorange 25 < 100 : Orange 5 < 25 : Yellow < 5 : Gray SC Solar Installations by County

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9 PV price is dropping NREL Report Shows Utility-Scale Solar PV System Cost Fell Nearly 30% Last Year September 12, 2017 Record-low costs enabled by decline in module and inverter prices

10 The cost of electricity

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12 Act 236: The Distributed Energy Resource Program Act Adopted in 2014, Act 236 is a balanced compromise bill developed by electric cooperatives, investor-owned utilities, solar power proponents and conservationists to open the way for more distributed energy production in South Carolina. Taken together, the bill s key provisions giving customers the freedom to lease solar, permitting utilities to introduce distributed energy programs, and ensuring equitable net metering rules are complimentary approaches that will expand customer options and increase cost effective renewable power in South Carolina. Enables Leasing of Solar Panels Act 236 allows homes and businesses to lease solar systems from independent solar companies and reduce their energy costs immediately. Solar leasing gives consumers independence, promotes market competition, and enables South Carolinians of modest means to access solar energy. Opens the Way for Utility Distributed Energy Programs Distributed energy resources like solar enhance grid security, increase consumer independence, and reduce health costs from pollution. Act 236 opens the way for utilities to get power from residential and commercial renewable installations as well as from utility-scale projects.

13 Sets Updated Net-Metering Rates Utilities, solar businesses, and conservation groups reached a settlement agreement in December on how rooftop solar will be treated for the foreseeable future in South Carolina. The settlement agreement is a critical step forward in implementing Act 236. Under the settlement, residential and commercial utility customers that install solar panels on their rooftops before 2021 will receive full retail credit for any excess power that flows back onto the electric grid and will be eligible to remain on this rate until December 31, 2025 without any solar-specific charges or fees. The settlement also establishes a methodology for valuing solar power for purposes of utility recovery of lost revenues, if any, which will be recoverable by the utilities through distributed energy resource programs that were authorized by Act 236. In 2020, the PSC will reevaluate the solar policies included in the settlement and will consider any appropriate changes at that time.

14 PV Leasing

15 Net Metering In its simplest form, net metering employs a standard electrical meter to record the flow of energy back and forth between a customer-generator and the utility s power grid. Net metering is usually created as an incentive for homeowners and small businesses to invest in renewable power systems. In many states, such as New Jersey and California, the programs are seeing hundreds of new participants each year, jump-starting new renewable energy service companies and creating robust markets for off-the-shelf solar and wind systems. Some worry about increased rates or safety problems, however there is no evidence that net metering has ever increased utility rates in any state or that an accident has occurred as a resulted from net metered renewable energy systems. Definition provided by the SC energy office

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17 Has Act 236 made an impact?

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23 WWTP Example The town of Silver City entered into a PPA contract with Affordable Solar, an Albuquerquebased solar provider, where the Town buys the power produced from the PV system at a set rate for a 20-year period. The savings on the electric bill for the Town and its citizens is estimated to be between 2 and 4 million dollars over the 20-year contract. These savings were calculated using the rate we were previously paying to the utility, the new lower flat rate we will be paying for the next 20 years, and predicting the increase in rates over that time period. The solar facility is owned, operated and maintained by Affordable Solar. The Town s only responsibility is to buy the power from Affordable Solar for 20 years. Because of ACT 236, no money out of pocket deals are now available here in SC, similar to the New Mexico WWTP above. SC does not allow PPAs but does allow leasing agreements that can accomplish the same thing. Plant is 3.2MGD and operates at 1.4MGD with annual bill of $280,000.

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25 A 9w LED equivalent could run for 111 hrs using the same amount of energy!

26 VISIBLE LIGHT.

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28 PV basics PV is most commonly made up of silicon wafers joined together to form a PV module (also called a panel ) and panels are then connected to form a solar array. The thin layers of silicon are: Similar to computer chips Much bigger Much cheaper Silicon is abundant Non-toxic Safe PV uses the visible light portion of the solar radiation Cell efficiency is typically defined as the percentage of solar energy falling on its surface that is converted into electrical energy.

29 PV basics con t Module efficiency is the combination of cells placed in a module. Many manufacturers typically point to these statistics to tout the prowess of their modules. However, true measure of a module is in Energy Yield. Energy Yield is the actual output in kwh as measured by the recording equipment over time.

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33 Monocrystalline PV Cell Made from a single large crystal, cut from ingots. Most efficient More expensive than poly Somewhat better in low light conditions Favorite for large projects or PPA s due to higher energy yield

34 Polycrystalline PV Cell Made from cast blocks of silicon which may contain many small crystals Less expensive than moly, making it the most popular Once set into frame with 35 or so other cells, efficiency difference is not as noticeable

35 Can go where modules cannot Requires more space for the same power output 35% less output than Mono

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38 PV rules of thumb PV modules vary greatly in wattage and size A typical standard module in the watt range is about 3 x5 in area Therefore the rule of thumb might be that each module is about 15 square feet. Assuming an average of 200 watts (they are getting higher), and using that thumb rule, a 1MW system should use 1.72 acres of module face. Actual ground use is around 2 acres. For South Carolina a good thumb rule for an entire system is annual kwh of a solar array is kw *1.4 x10^3 Ex: a 5kW system should produce 7000kWh annually.

39 Penetrating Ground Mount Ballasted Ground Mount Penetrating Roof Mount Ballasted Roof Mount Carports Specialty Mounts Grid Connected Off Grid Stand Alone Types of Solar Installs Grid Connected with Battery Backup Grid Connected with Alternate Energy Storage Grid Connected with Grid Zero Inverter Remains synchronized with grid at all times, seamless

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52 Size the system Total annual kwh Divide by 365 to get daily usage Divide by sun hours Derate (usually 70% - 80% because it is not always sunny) This will give you the total kw that is needed. Plug this into PVwatts to verify Example: 90,000kWh Annual usage 90,000/365= 247 kwh per day 247/4.5 (sun hours) = 55kW Derate at 70% = 55/.7 = 79kW system required Have a few solar vendors do this to see how close their size compares to one another. Have them explain any differences in methodology and why. You can also experiment with Pvwatts (the solar vendors will be using it also) and get results.

53 PVWatts

54 Azimuth Installation Considerations Elevation Orientation and Tilt Environment (dirt, dust, foreign debris) Distance to POI (Point of Interconnect) Shading of the array Geographical Mean Temperature and Solar Insolation Structural analysis and roof age Maintenance

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56 2-4 acres/mwp acres/mwp

57 Battery Back-up/Storage Battery backup/storage typically doubles the price of a PV installation As storage prices drop, it will become a serious game changer.

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59 Energy Efficiency as an energy source is the best place to start!

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62 Energy Efficiency for Water and Wastewater Systems Always start here to minimize size of solar system. Can have very low payback. Premium motors VFDs LEDs Demand Strategy Programmable thermostats Geothermal (use of WWTP effluent or WTP influent) for water cooled HVAC More efficient aeration technology More efficient HVAC technology Minimize I & I and system leakage Closed loop control systems. Examples: DO Pressure flow

63 Funding DSIRE: Database of State Incentives for renewables and efficiency

64 State Revolving Fund (SRF) and USDA Within the SRF is a green component that allows for lower interest rates for projects that qualify as green project reserve (GPR). Some of the SRF money has to be allocated to these projects. Usually these projects are broken out from larger projects. The USDA also has funding available for green projects in rural areas.

65 ConserFund from the SC Energy Office Low-cost loan program (currently 2%) available for energy efficiency improvements in State Agencies Schools Public Colleges and Universities Private Non-profit Organizations Loans available for 100% of eligible project costs Projects can be lumped together under one loan (in fact it is encouraged!) As long as payback is 8 years (can sometimes be stretched to 10) or less, support fees (such as energy audit or engineering) can be rolled into the loan. $25,000 minimum and $500,000 maximum per year

66 ConserFund Advantages The biggest advantage of ConserFund is the loan structure Loans are structured so that the loan can be repaid out of utility bill savings Because of this, the loan presents a net savings on your annual budget- You save more than you pay! Loan repayment starts after project completion so that utility savings can accrue before you make any payments on your loan Payments can be delayed for up to a year after project is completed.

67 Private Financing Company Contact Energy Efficiency Financing Phone # Office Cell These companies specialize in no money out of pocket energy efficiency financing. Susquehanna Finance Paul Lee paul.lee@susquehanna.net Eco-Tech Funding Emanual Dewick manny@eko-techfunding.com Graybar Kevin Benson Kevin.Benson@graybar.com proposal tool Northwrite Agile Volt Patrick O'Neal poneill@northwrite.com *MESA Infinite Energy Solutions Ted Eschrich ted@ies-led.com Enerlinc Matthew Smith msmith@enerlinc.com Building Energy Ross Reida ross.reida@buildingenergy.com Ascentium Capital Alex Depping AlexDepping@AscentiumCapital.com Noesis Kerin LeClair *Managed Energy Services Agreement Ext:1170 kleclair@noesis.com Notes Municipal Service Contracts / Shared Savngs Annual Contract Fee but many additional support services

68 Resources General, Site Survey NREL: SC Energy Office: Funding: Pvwatts: Energy Information Association (EIA): Database of State Incentives for renewables and efficiency:

69 Questions?