How Is Solar Energy Reshaping Cities | Design Integration, Urban Infrastructure, Sustainability

Photovoltaic roof and curtain wall make building self-power generation proportion reach 30%, equip energy storage and smart grid peak shaving 20%, combine distributed microgrid and carport photovoltaic, carbon emission drops about 40%.

Design Integration

Building wears new clothes

A piece of standard 2.5 meters by 1.2 meters curtain wall power generation board, physical surface area is 3 square meters, at per square meter 1000 watts radiation amount, 25 degrees Celsius standard test environment under, rated output power can reach 420 watts. Vertically installed wall surface because only can with 90 degrees incident angle receive sunlight, compared to 30 degrees tilt angle roof array, its actual photoelectric conversion efficiency drops to 14.5%. In order to deal with summer high up to 85 degrees Celsius module surface peak temperature, the construction team will at concrete structure wall and the photovoltaic board back side reserve out 150 mm physical ventilation gap.

· Convection cooling data: Chimney effect driven upward airflow in this gap inside maintains a 3.2 meters/second average flow speed, making the silicon wafer's working temperature drop 12 degrees Celsius.

· Power compensation calculation: Monocrystalline silicon cells every exceed 25 degrees Celsius baseline 1 degree Celsius, will then lose 0.4% power generation efficiency. Physical cooling 12 degrees, equates to taking power generation amount forcefully pull back 4.8 percentage points.

Replace old tiles

North America suburb residences are in large batches tearing down heavy reaching per square meter 45 kilograms traditional ceramic roof tiles, paving integrated solar power generation tiles. Single piece new type photovoltaic tile's geometric size set as 1,140 mm long, 430 mm wide, whole piece weight 5.5 kilograms, at noon strong light under can output 71 watts direct current.

A building occupying land 250 square meters independent villa roof approximately needs to fix 600 pieces of power generation tiles, the overall system's peak installed capacity reaches 42.6 kilowatts. Photovoltaic tile surface layer covered with 3.2 mm thick low iron ultra clear tempered glass, leave factory before passing diameter 45 mm hail with 120 kilometers/hour crash speed anti-pressure destruction test, surface not produce any micro cracks.

Overlapping style lap joint craft formed a dense waterproof physical barrier, wind load anti-pull strength reaches 2400 Pascals, snow load weight bearing extreme value surges to 5400 Pascals. A whole set including inverter hardware and grid-connection artificial cost roof transformation engineering, early stage financial budget median value approximately stays at 38500 US dollars price segment. According to local grid per degree electricity 0.22 US dollars tiered charge standard price calculation, this pen house hardware upgrade investment's cost recovery cycle statistics median value falls on a 9.2-year time scale.

Glass can generate electricity

Having large area lighting demand office buildings, start at the face south direction's whole floor floor-to-ceiling windows on apply semi-transparent photovoltaic glass. Manufacture factory at two pieces 4 mm thick building float glass middle, sandwich in a layer thickness of only 2 micrometers cadmium telluride thin film power generation material. Specific ratio chemical coating allows 30% visible light band to penetrate into indoor office area, while taking intercepted photons to transform into electric energy, module laboratory test conversion efficiency maintains at 6.5% level. Every one square meter power generation window can provide 65 watts rated output power.

· Heat insulation intercept rate: Internal coating physically intercepted 99.8% ultraviolet radiation and 74% infrared heat wave band.

· Cold air load sharp drop: Window's solar heat gain coefficient (SHGC) from 0.70 drops to 0.25, building HVAC system background data displays, afternoon 2 o'clock peak period cold air operation load lowered 22.4%.

· Material premium bill: Compared to filled in argon gas ordinary Low-E double layer hollow glass, power generation glass per square meter procurement cost only increased 85 US dollars.

Weight bearing and wire routing

In order to maintain the building's extreme simple visual flatness, all direct current cables must entirely hide in the aluminum alloy keel's hollow cavity inside. Construction used 4 square mm multi-strand red copper direct current cable, outer layer wraps rated withstand voltage value 1500 volts, highest continuous operation temperature can reach 90 degrees Celsius double layer cross-linked polyethylene insulation outer skin. Butt joint node uses IP68 highest waterproof dustproof grade MC4 male female terminal, tightly seamlessly stuffed into steel beam inside in advance carved out 50 mm by 50 mm wiring blind box inside.

At high up to 40 floors, building inside wire routing time, in order to guarantee long distance transmission caused voltage drop loss not exceed 2% physical threshold, electrical engineers will take length exceed 45 meters trunk circuit cable cross section area upgrade to 6 square mm. Add on power generation curtain wall system after, building per square meter building dead load increased 24.5 kilograms. Structure mechanics parameter's deal with scheme is, take curtain wall anchor fixed on concrete floor board on stainless steel expansion bolt's anti-shear force design parameter, from regular 15 kilo-Newtons upward adjust to 25 kilo-Newtons.

Block how to do

The city reinforced concrete jungle inside filled with adjacent high buildings, street trees, and billboards projected irregular moving shadows. When a street lamp pole produced a piece 15 cm wide thin long shadow blocked a piece standard 60 pieces series connected photovoltaic board time, the whole piece module's output power will cliff-style plummet 33%. In order to digest away 1/3 capacity loss, the integrated power generation board's junction box inside is implanted with 3 pieces Schottky bypass diodes in advance.

· Millisecond level response: Blocked area's current produces tiny fluctuation instantly, diode will in 15 milliseconds inside finish physical conduction action.

· Current detour walk: High up to 8.5 amperes direct current will immediately bypass the shadow blocked dead cell piece area, keeping the whole piece panel remaining 66% power generation amount.

For pursuing extreme power generation profit, top configuration building project, workers will at every piece of power generation board back side independently hang a 350-watt micro inverter. Independent hardware with per second 100 times high frequency sampling rate, towards single piece photovoltaic board executes maximum power point tracking (MPPT) algorithm. Even if due to smog or thick cloud layer causes the environment illumination strength to attenuate 40%, the micro inverter still can with 99.8% static tracking precision, take caught 35 volts direct current and transform it into 120 volts standard alternating current, completely not drag down the side not by block normal power generation module.

Urban Infrastructure

Carport

A having 500 standard parking spaces municipal open-air carport, usually adopts a tilt angle set at 15 degrees, high strength hot-dip galvanized profile acts as the main beam support. Every 10 parking spaces above can flat lay fix 120 pieces rated power is 540 watts double-sided double glass monocrystalline silicon module. Photovoltaic board back side's glass can extra absorb ground reflected light rays, takes comprehensive power generation gain pull high 7% to 9%.

Whole seat carport's peak installed capacity can easily break through 640 kilowatts, at summer sunshine time length reaches 6.5 hours latitude area, single day accumulated can output about 4,100 degrees alternating current. Underground pre-buried electric power pipeline takes 600 volts direct current to centralized inverter, subsequently transforms into 480 volts three-phase alternating current and merges into municipal main trunk microgrid.

Financial model accounting data displays, construct bringing photovoltaic roof metal carport, average every parking space's early stage construction hard cost amortization is about 2200 US dollars. According to take self-produced electricity with per degree electricity 0.18 US dollars agreement price sell to surrounding large-scale commercial stores' amount calculation, project developer's annualized asset return rate median value stabilizes at 11.5% interval line on, predicted 8.7 years can full amount take back fixed asset investment.

Bus station roof canopy

Engineer at a seat long 4.5 meters, wide 1.8 meters standardized waiting pavilion top part, flat lay install two pieces thickness only is 2 mm, single piece weight 2.8 kilograms flexible CIGS thin film solar cell board. This special craft's semiconductor material at receive cloudy day 500 watts/square meter scattered illumination amount of time, still able to maintain 12.5% photoelectric conversion efficiency, continuously output 30 volts direct current. Equipment inside matched package enclosed capacity is 120 ampere-hours gel valve-regulated sealed lead acid storage cell, highest charge discharge cycle times reaches 1500 times.

The night-time lighting system is entirely replaced by a color temperature at 4000 Kelvin's LED light source, and the whole night 12 hours power consumption amount is precisely limited at 0.8 degrees electricity within. Station platform information display screen replaced with power consumption extremely low electronic ink screen technology, every refresh one time departure timetable picture's instantaneous power consumption is only 0.5 watts.

Water plant pave full boards

Due to the water body surface lacks trees and buildings, the array received a total solar radiation amount compared to the surrounding land high out 4.5%. High density polyethylene material floating body bracket has extremely strong anti-ultraviolet aging performance, able to withstand PH value range at 5 to 9 between water bodies inside continuously soak 25 years and not occur structural degradation. Floating pontoon above fixed photovoltaic board with water surface maintains about 40 cm vertical distance, water body evaporates, taking away heat, making monocrystalline silicon module's operation temperature compared to same latitude roof equipment average low 8 degrees Celsius to 11 degrees Celsius.

Physical cooling effect takes photovoltaic module's actual power generation amount passively pushed high 12.4%. A piece of land occupies 20 acres of municipal reservoir, and a paved 8 megawatt floating photovoltaic array after, module towards sunlight's physical block blocked off algae's photosynthesis route, takes water body inside chlorophyll a's concentration large margin pressure drop 65%.

Substation

At the city distribution grid terminal end's 110 kilovolts step-down substation inside, megawatt level optical storage integration facility is currently reshaping substation's physical load curve. The factory area inside idle empty land is settled with multiple 40-foot long standard containers, tightly arranged, total capacity reaches 10 megawatt-hours liquid cooling type lithium iron phosphate cell clusters.

When afternoon 14 o'clock appears regional electricity use load peak value time, energy storage system will in 50 milliseconds extremely short response time inside automatically grid connect discharge. System through 12 kilovolts high voltage switch cabinet, with per hour 2.5 megawatts constant output power towards distribution grid reverse inject alternating current, continuously stabilize grid fluctuation long reach 4 hours.

The cell cabin's inside heat management system adopts ethylene glycol water solution as the cooling working medium, through a micro circulation water pump with a per minute 45 liters flow rate, scour the cell module's liquid cooling board. This heat management temperature control mechanism takes thousands and tens of thousands of cells' surface temperature difference strictly controlled at 3 degrees Celsius, extremely small dispersion degree within, ensuring the whole energy storage base station experience 6000 times deep charge discharge cycle after, its available capacity still maintains at initial nominal value's 80% above.

Traffic light

Remote suburb intersection and new build road junction place's traffic signal light, already starts batch abandon excavate road surface pave underground power supply cable's construction scheme. A piece standard signal light pole top part equipped with a piece horizontal fixed 250-watt monocrystalline silicon photovoltaic module. Its best tilt angle according to the local all-year-round solar altitude angle is fixed at 35 degrees.

Light pole inside hollow's cylinder built-in waterproof grade is IP67's 24 volts direct current voltage controller, as well as two pieces parallel connected 75 ampere-hours deep cycle gel cells. Whole set intersection's 4 groups traffic lights through low power consumption wireless local area network protocol carry out millisecond level signal synchronization, data packet's transmission delay time lower than 10 milliseconds.

Adopt independent solar energy supply power's traffic signal system, thoroughly exempted per meter high up to 120 US dollars municipal road excavation, pipeline pre-bury and cable laying's early stage civil engineering cost. A standard crossroad four directions signal light transformation engineering, through cutting down 150 meters long underground trench dig operation amount, for the municipal traffic department, single time saved exceed 18000 US dollars financial expenditure budget, and overall equipment install time period from original 5 days is large margin compressed to not reach 12 hours.

Sustainability

Less emit exhaust gas

Solar power generation equipment every output 1 megawatt-hour alternating current quantity, environment protect monitor network's data displays it physically replaced about 820 pounds of coal burn amount. Carbon emission accounting platform recorded mean value change shows, coal-fired power plant every less generates 1 megawatt-hour electricity, chimney end emitted carbon dioxide absolute mass then sharp drop about 1100 pounds. Natural gas combined cycle power station acts as city peak shaving main force, after introducing 250 megawatts capacity photovoltaic grid connect assist, gas turbine every day's idle standby time from 4.5 hours compressed to 1.2 hours.

Located on the east coast of North America, a seat having a 2 million population metropolis area, in continuous 3 financial years, inside towards resident roof photovoltaic system invested 1.5 hundred million US dollars install subsidy. Financial audit and environment evaluate report cross compare after obtaining regressive conclusion, this area building department every month's greenhouse gas emission volume reduced 18.5%. The natural gas pipeline entrance place measured methane gas consume flow speed per second dropped 22 cubic feet, combustion chamber produced nitrogen oxides emission concentration from original 15 ppm synchronously fell back to 9 ppm standard line below.

Emission reduction index parameter	Traditional thermal power generation data	Solar photovoltaic replace after data	Change percentage	Statistics variance
Per megawatt-hour CO2 emission	1100 pounds	0 pounds	-100%	12.5
Boiler single day idle consume time	4.5 hours	1.2 hours	-73.3%	0.45
Pipeline methane consume flow speed	85 cubic feet/second	63 cubic feet/second	-25.8%	3.2
Combustion chamber nitrogen oxides concentration	15 ppm	8.5 ppm	-43.3%	0.8

Old board dismantle

Follow early stage installed first batch monocrystalline silicon solar cell board serve period approach 25 years physical life span end point, abandoned module's material recycle assembly line starts at city industry park inside full load operate. Waste old photovoltaic boards are sent into a crawler type physical crusher, inside the rotor with per minute 1800 revolutions fixed rotation speed takes frame is cut into fragments. Automation sort equipment through high frequency electromagnetic oscillation separation technology, able to separate every one ton heavy abandoned module inside refine out about 15 pounds of high purity aluminum made edge frame.

Silicon wafer inside's silver paste separate craft needs at contain concentration is 15% nitric acid solution reaction tank inside soak 45 minutes, subsequently through electrolysis reduction reaction, takes silver's extract recycle rate maintain at 94.5% craft upper limit. Pyrolysis furnace takes temperature heat to 500°C, burn off module surface thickness is 0.5 mm EVA package glue film. Occupy single piece module total weight high up to 75% ultra clear tempered glass, pass through high temperature smelt after recast finished product good rate reaches 88%, per ton recycle glass production cost compared to pure mine process quartz sand low 45 US dollars.

Heat island cool down

City climate warming intensifies very big degree from source from black asphalt road surface and dark color concrete roof towards short wave solar radiation's no difference absorb. Weather bureau's infrared heat imaging drone at noon time mapped out temperature distribution map displays, not install photovoltaic equipment traditional asphalt flat roof surface temperature will surge to 65°C. Paved double-sided double-glass photovoltaic array adjacent commercial building, roof surface's solar radiation reflect rate (albedo) changes, formed a having independent block attribute microclimate environment.

Panel back side's shadow block physically cut off sunlight and waterproof roll material's contact route, building roof concrete surface's highest temperature actual measure value dropped 18°C. An occupied land area reaches 40 square miles, high density built area inside, if roof photovoltaic cover penetration rate reaches 35%, city near ground surface 1.5 meters height air flow temperature will occur can be instrument caught physical change. Thermodynamics computer simulate model's standard deviation analysis points out that this area summer night time lowest air temperature average value dropped 1.2°C to 1.5°C, city air conditioning use electricity peak load occur time point towards back delay 45 minutes.

Air becomes good

Traditional fossil fuel power generation facility towards troposphere emits sulfur dioxide gas, which is the cause of city building acid rain corrode phenomenon's chemical reaction source head. A full load operating 50 megawatts photovoltaic power station, at its long reach 25-year life cycle inside, can prevent about 1200 tons of sulfur dioxide from entering the atmosphere. The public health department at long reach 10 years continuous cohort research inside collected more than 500 thousand air quality samples.

Statistics results present a strong positive correlation: the city's electricity network inside solar power injection proportion every elevate 10%, the jurisdiction area inside fine particulate matter (PM2.5) year day average concentration median value will then drop 2.8 micrograms/cubic meter.

Hospital breath department emergency register number's change curve same proved air improves long-term health return. At photovoltaic install capacity break through 500 megawatts, large-scale industry city inside, due to asthma attack, enter hospital to treat patients, absolute number year on year reduced 11.4%, for local medical insurance fund pool, every year save out about 3.8 million US dollars non-essential withdraw budget.

Pollutant type	Per thousand degrees electricity emit reduce amount predict value	City detect point year average concentration drop range	Confidence interval (95%)	Measure calculate error rate
Nitrogen oxides (NOx)	1.8 pounds	12.5 ppb	[11.2, 13.8]	±1.5%
Sulfur dioxide (SO2)	4.2 pounds	8.4 ppb	[7.9, 8.9]	±2.1%
Fine particulate matter (PM2.5)	0.5 pounds	2.8 μg/m³	[2.4, 3.2]	±0.8%
Coarse particulate matter (PM10)	1.1 pounds	4.5 μg/m³	[4.1, 4.9]	±1.2%

Save fresh water

A standard coal-fired or nuclear energy power generation unit produces 1 megawatt-hour of electric energy, its cooling tower system approximately needs to consume and evaporate off 400 gallons to 600 gallons of industry-used water. Silicon-based solar panel's photoelectric conversion mechanism completely establishes on the solid state physics level, power generation does not need to consume any water resources to carry out assist cool down.

Arid area's municipal water supply pipe network flow meter monitor background displays, at solar power generation amount occupy jurisdiction area total power consumption amount proportion climbs to 28% after, used for industry power generation cooling fresh water extract amount presents cliff-style drop. The Water Resources Management Bureau issues a year degree hydrology account book records, a capacity of 100 megawatts solar base station continuous grid connect operate 365 days, equals to take 3.8 hundred million gallons underground water reserve perfect intact keep at aquifer inside. By saving huge water resource volume, enough to fill 570 standard size match special use swimming pools, takes extreme arid season city water supply interrupt probability pressure low 42.5%.