Installing solar on an industrial unit is not a scaled-up version of a residential installation. It is a fundamentally different engineering and regulatory exercise — one that involves three-phase power systems, DISCOM high-tension approvals, structural load calculations on industrial sheds, demand charge management, and often co-ordination with multiple contractors across civil, electrical, and grid interconnection workstreams.
Getting it wrong at any stage delays commissioning, increases cost, and can result in a system that under-performs for years. Getting it right — with proper load analysis, engineering design, equipment procurement, and commissioning discipline — produces a system that delivers predictable returns across a 25-year plant life.
This guide walks through the complete industrial solar installation process from the initial load audit to handover and long-term O&M, with clear explanations of what happens at each stage, what decisions are made, and what documents you will need.
Direct answer. Industrial solar installation follows eight distinct stages: load audit, site survey, system design, equipment procurement, civil and structural work, electrical installation, DISCOM coordination, and commissioning with handover. For a 100–500 kW rooftop system, the full process from first site visit to energisation typically takes 8–14 weeks for straightforward DISCOM jurisdictions. Each stage has specific regulatory and engineering milestones that cannot be bypassed without risk to the project’s performance and compliance.
The Heaven Green Industrial Solar Commissioning Ladder
The Heaven Green Industrial Solar Commissioning Ladder is an eight-rung framework that maps the complete industrial solar project from first analysis to live operation. Each rung must be completed before the next begins — skipping or abbreviating a rung creates downstream problems that are significantly more expensive to fix than to prevent.
Rung 1 — Load Audit: Analyse the factory’s actual electricity consumption, demand patterns, and tariff structure to define the right system size.
Rung 2 — Site Survey: Assess the physical site — roof structure, orientation, shadow sources, cable routing, and switchroom access — to confirm what can actually be built.
Rung 3 — System Design: Produce the detailed engineering design — string layout, inverter configuration, cable sizing, single-line diagram, and generation model.
Rung 4 — Equipment Procurement: Source panels, inverters, mounting structures, and electrical BOS components from verified, ALMM-listed suppliers with confirmed lead times.
Rung 5 — Civil and Structural Work: Prepare the mounting structures, waterproofing, civil foundations (for ground mounts), and any roof reinforcement required.
Rung 6 — Electrical Installation: Install panels, inverters, DC cables, AC cables, protection equipment, and monitoring systems according to the approved design.
Rung 7 — DISCOM Coordination: Submit applications, technical documents, and inspections with the distribution company to obtain net metering approval and grid synchronisation permission.
Rung 8 — Commissioning and Handover: Perform energisation tests, performance verification, safety checks, operator training, and formal documentation handover.
Why Industrial Solar Is Different from Residential
The surface similarity between a 5 kW home system and a 500 kW factory system misleads many buyers. The underlying engineering, regulatory, and commercial complexity is fundamentally different in several dimensions.
Three-phase power systems. Industrial units almost universally operate on three-phase LT or HT supply. The solar plant must be designed to inject power symmetrically across all three phases to avoid unbalanced loading, which can damage motors and sensitive equipment. Residential systems on single-phase supply do not face this constraint. Three-phase inverter selection, phase balancing, and protection relay settings are industrial-specific design decisions.
High-tension (HT) connections. Factories consuming more than approximately 50 kW typically have HT (11 kV or 33 kV) connections rather than the LT (415V) connections used by homes. Solar generation is at LT voltages and must be connected at the LT bus on the load side of the HT/LT transformer. This determines the maximum solar capacity relative to the transformer size and has implications for injection limits and DISCOM approvals.
Demand charges and contract demand. Industrial tariffs in Gujarat and most states include a significant “demand charge” component — a fixed monthly charge based on maximum kVA demand recorded in any 15-minute interval during the billing cycle. Solar, by offsetting peak demand periods, can meaningfully reduce demand charges — but only if the system design accounts for load profile matching. Poorly designed systems that generate mainly at midday while the factory’s peak demand occurs in morning or evening sessions can miss most of the demand charge saving.
Scale of roof and structural complexity. Industrial shed roofs are often large-span metal sheet or RCC structures with complex structural profiles, drainage patterns, and load-bearing limitations. A detailed structural assessment by a licensed civil engineer is non-negotiable before any mounting work begins.
Longer regulatory approval process. Industrial DISCOM approvals involve HT inspections, feeder load assessments, protection relay co-ordination, and sometimes 132 kV substation-level approvals for very large systems. These add 4–10 weeks to the project timeline compared to a residential installation. Our detailed guide to solar commissioning in Gujarat covers the DISCOM approval timeline in detail.
Rung 1: Load Audit and Demand Analysis
The load audit is the engineering foundation of the entire project. Without accurate load data, every subsequent decision — system size, inverter selection, AC cable sizing, and financial projections — is built on guesswork.
What a proper industrial load audit covers:
-
12-month electricity bill analysis: Extract monthly consumption (kWh), maximum demand recorded (kVA/kW), power factor, and tariff components (energy charge, demand charge, fuel adjustment charge, fixed charge). Identify seasonal peaks and troughs.
-
Half-hourly demand profile: If your DISCOM meter records 15-minute or 30-minute demand data (TOD meters, trivector meters, ABT meters), obtain 12 months of this data. This is the most valuable input for solar sizing — it shows exactly when your factory consumes power through the day and how that aligns with solar generation windows.
-
Load categorisation: Identify which loads are base loads (running 24×7), shift-sensitive loads (operating during certain hours only), and demand-spike loads (motors starting, compressors cycling). Solar can reliably offset base loads and daytime shift loads; it cannot reliably offset night-shift loads or loads heavily concentrated outside solar hours.
-
Power factor analysis: Industrial units with large induction motors often operate at power factor 0.7–0.8. Poor power factor inflates apparent demand (kVA) and can incur tariff penalties. Solar installation is often a natural opportunity to also assess and improve power factor — these two projects can share civil and electrical infrastructure.
-
Future load growth assessment: A factory that will double its production capacity in three years has very different solar sizing requirements from one with stable operations. Size for Year 3–5 consumption, not just current consumption, within the constraints of available roof space and sanctioned load.
The output of the load audit is a Solar Sizing Report — a document that specifies the recommended system capacity (kW peak), expected annual generation (kWh), grid offset percentage, and expected impact on demand charges. This report drives every subsequent engineering decision.
Rung 2: Site Survey
The site survey translates the load audit’s sizing recommendation into a feasible physical design. It is a field assessment conducted by qualified structural and electrical engineers, not a sales visit.
Roof structure assessment:
- Material (RCC slab, metal sheet, asbestos sheet, polycarbonate)
- Structural drawings and load-bearing capacity certification from original builder
- Existing penetrations, drainage patterns, and waterproofing condition
- Access points for installation and future maintenance
Warning: Asbestos Roofs Require Special Handling
Older industrial sheds in Gujarat frequently have asbestos cement sheet roofing. Solar installation on asbestos roofs is technically possible but requires specialised mounting hardware that avoids drilling, structural assessment for additional load, and careful project management to comply with occupational health regulations on asbestos disturbance. Any EPC contractor proposing to drill-mount on asbestos sheets without an asbestos survey is cutting corners that could create serious liability.
Shadow analysis: Using sun path simulation software (PVSyst, Helioscope, or equivalent), the survey team maps all shadow sources — parapet walls, water tanks, ventilation exhausts, elevator shafts, adjacent buildings — and their impact on panel rows at different times of day and seasons. Shadow analysis determines the optimal panel layout and estimates the shadow loss as a percentage of potential generation. Industrial installations with poorly managed shadow can lose 15–25% of generation.
Electrical switchroom survey: Confirm the location of the existing LT switchboard, available space for inverter and protection equipment installation, the HT/LT transformer rating and available capacity headroom, and the path for AC cable routing from roof to switchroom.
Survey output: A detailed site survey report with as-built drawings of the roof, shadow analysis results, structural assessment, electrical connection point, recommended panel layout, and a preliminary cable routing plan.
Rung 3: System Design
With the load audit and site survey complete, the system design translates the analysis into a formal engineering document set that drives procurement and installation.
Key system design deliverables:
- DC string layout drawing: Maps exactly which panels are in which strings, connected to which MPPT input of which inverter. Accounts for panel orientation, shadow avoidance, and minimising cable lengths.
- Inverter selection and configuration: For industrial systems above 100 kW, central inverters (100 kW+) or multiple string inverters with remote monitoring are typical. The design specifies inverter count, rated capacity, protection relay settings, and communication protocol.
- Single-line diagram (SLD): The master electrical drawing showing the complete AC and DC circuit from panel strings through combiner boxes, inverters, AC protection boards, to the grid connection point. This document is submitted to the DISCOM for approval.
- Cable sizing calculations: DC cables are sized for maximum short-circuit current; AC cables for continuous rated current with appropriate voltage drop limits (typically maximum 1.5% DC side, 1% AC side).
- Generation model: A 25-year energy yield forecast using PVSyst or equivalent software, incorporating site-specific irradiance data (from NASA POWER or NISE data sets), shadow losses, temperature derating, soiling losses, and inverter efficiency curves. The generation model is the financial projection basis.
- Structural design for mounting: Confirmation of mounting structure type (ballasted, drilled flange, standing seam clamp for metal roofs), anchor load calculations, and sign-off from a licensed structural engineer.
The system design is reviewed internally by a senior engineer and then externally (by the DISCOM’s engineering team) before installation begins. Approved design changes after installation starts are extremely expensive — discipline at the design stage is critical.
Rung 4: Equipment Procurement
For industrial systems above 100 kW, equipment procurement is a structured supply chain management exercise with lead time implications that affect the project timeline.
Solar panels: Order panels from ALMM List I manufacturers with confirmed delivery dates. For 100–500 kW projects, panel delivery typically requires 2–4 weeks lead time if sourcing from stock. For larger orders, 6–8 weeks for factory-direct supply. Verify that the panels delivered match the certified model number exactly — substitution of variants post-order is a known risk. Our guide to industrial solar solutions in Gujarat covers equipment specification in more detail.
Inverters: Industrial-grade string or central inverters with remote monitoring, data logging, and RS485/Ethernet communication for SCADA integration. Lead times: 3–6 weeks for common models. Confirm warranty terms — 5-year standard warranty is the minimum; 10-year extended warranty is available from most reputable brands and worth the premium for industrial systems.
Mounting structures: Hot-dip galvanised (HDG) steel is standard for industrial systems due to its resistance to corrosion in industrial atmospheric conditions. Aluminium mounting is lighter but can react with galvanised iron roofing materials. The design engineer specifies the material; procurement must match exactly.
Electrical BOS (Balance of System): AC and DC cables (copper for main runs, rated for outdoor UV exposure), combiner boxes, DC string fuses, surge protection devices (SPD) on both DC and AC sides, AC switchboard, energy meters for generation monitoring, and communication gateways.
Documentation at procurement stage: Manufacturer test certificates, BIS certificates, ALMM listing confirmation, packing lists, and warranty cards. These documents are needed for DISCOM submission and post-installation insurance.
Rung 5: Civil and Structural Work
Civil work on industrial solar projects precedes electrical installation and can take 1–3 weeks depending on scope.
Typical civil scope for rooftop industrial installations:
- Roof waterproofing repairs and recoating at penetration points (critical for metal and RCC roofs)
- Installation of mounting structure base plates and anchor bolts (for drilled mounting)
- Civil foundation blocks for ground-level inverter skids or weatherproof inverter enclosures
- Cable tray installation along roof surface and down external building walls to switchroom
- Conduit installation through walls or roof for HV cable routing
- Earthing and lightning protection electrode installation
For ground-mounted industrial systems:
- Site clearing and levelling
- Pile driving or concrete pedestal foundations for mounting frames
- Access road construction for O&M vehicles
- Security fencing and perimeter lighting
Tip: Waterproofing Before Mounting Is Non-Negotiable
Every roof penetration for a mounting anchor is a potential water ingress point. Waterproofing sealant applied during civil work is cheap; water damage to a factory interior after a monsoon season because of unsealed penetrations is expensive and creates massive goodwill damage for the EPC contractor. Insist on waterproofing of all penetrations using appropriate sealant (polyurethane or silicone depending on roof material) before any mounting hardware is fixed.
Rung 6: Electrical Installation
The electrical installation phase is the most technically demanding and must be executed by licensed electrical contractors holding appropriate government certifications.
DC-side installation sequence:
- Mount solar panels on completed structural framework, checking each panel for physical damage before mounting.
- Connect panel strings per the approved string layout drawing.
- Route DC cables in UV-rated conduits or cable trays from panel arrays to combiner boxes.
- Install combiner boxes (string fuses, SPD, DC disconnect) at roof level.
- Route DC main cables from combiner boxes to inverter DC input terminals.
- Verify open-circuit voltage (Voc) and short-circuit current (Isc) of each string before connecting to inverter.
AC-side installation sequence:
- Install inverters in weatherproof enclosures or switchrooms per design.
- Connect AC output from inverters to AC switchboard with appropriate circuit breakers and protection relays.
- Install net metering point (bidirectional energy meter as specified by DISCOM).
- Commission anti-islanding protection settings per DISCOM requirements.
- Install monitoring hardware (data loggers, communication gateways, CT sensors).
Earthing and lightning protection: Industrial solar systems require a comprehensive earthing system connecting the panel frames, mounting structures, inverter chassis, and AC switchboard to the facility’s main earth grid. A dedicated lightning protection system (LPS) may be required for roof-mounted systems on tall structures — assess per IS 2309 and IEC 62305.
For systems connecting to the grid at LT level, this is typically the final stage before DISCOM inspection. For HT-connected factories, the engineering of the grid connection point involves additional protection relays and may require a dedicated power quality study.
Rung 7: DISCOM Coordination
The DISCOM coordination stage is where many industrial solar projects lose weeks or months due to paperwork gaps, incorrect form submission, or failure to meet technical requirements. Understanding the process in advance dramatically reduces delays.
Typical DISCOM approval process for industrial solar in Gujarat (MGVCL, UGVCL, DGVCL, PGVCL):
| Stage | Action Required | Typical Timeline |
|---|---|---|
| Pre-approval application | Submit load details, proposed system capacity, SLD | 2–4 weeks for initial review |
| Technical feasibility check | DISCOM checks feeder capacity and transformer headroom | 2–4 weeks |
| Net metering agreement | Sign net metering agreement and pay security deposit | 1–2 weeks |
| Inspection scheduling | DISCOM engineer inspects completed installation | 2–4 weeks (scheduling dependent) |
| Meter installation | Bidirectional meter installed by DISCOM | 1–2 weeks after inspection |
| Commissioning order | DISCOM issues written permission to energise | 1 week |
The critical pre-approval step often catches projects that have already procured equipment — the feeder may not have capacity for the proposed injection, requiring a redesign of the system size or connection topology. Always complete the DISCOM feasibility check before finalising equipment procurement orders.
For net metering specifics, including the regulatory framework and benefit calculation, see our dedicated net metering in India guide. The full Gujarat permit and approval process is covered in solar permits in Gujarat.
Regulation: Industrial Net Metering Cap in Gujarat
In Gujarat, net metering for LT industrial consumers is permitted up to the sanctioned load. For HT consumers, the injection limit is set by the DISCOM's feeder capacity assessment. Systems above 1 MW may require open access approval rather than net metering. Always confirm the applicable regulatory framework for your sanctioned load and connection type before designing the system.
Rung 8: Commissioning and Handover
Commissioning is the formal process of energising the solar plant, verifying that it performs as designed, and handing over a fully documented, trained system to the owner.
Commissioning checklist for an industrial solar plant:
- Confirm all DC string Voc and Isc values match design tolerances (within 3%)
- Verify inverter startup sequence and grid synchronisation on each unit
- Check anti-islanding protection — manually test that inverters disconnect within required response time when grid is removed
- Verify energy meters (generation meter, export/import meter) are recording accurately
- Check protection relay settings against the approved protection coordination study
- Verify earthing resistance values are within IS 3043 / IEC 60364 limits (typically below 1 ohm for industrial systems)
- Test monitoring system — confirm data from all inverters is reaching the monitoring platform
- Check surge protection devices on DC and AC sides are intact and operational
- Verify fire safety measures — cable tray fire stops, inverter room ventilation, fire suppression if applicable
- Document as-built drawings reflecting any field changes from design
Performance verification: At commissioning, actual generation under current irradiance conditions is compared to the PVSyst model prediction for those conditions. A commissioning performance ratio (PR) test checks that the system efficiency is within acceptable bounds of design (typically PR above 75% for an industrial system in standard conditions). A low PR at commissioning flags installation or equipment issues before they become 25-year performance problems.
Handover documentation package:
- As-built single-line diagram
- Equipment datasheet set (panels, inverters, mounting structures)
- Certification documents (BIS, IEC, ALMM)
- DISCOM approval letter and net metering agreement
- Warranty certificates and contact details
- O&M manual with maintenance schedule
- Monitoring system access credentials
- Commissioning test reports
Our detailed guide to solar commissioning in Gujarat covers the inspection and handover process in detail.
Planning an industrial solar installation for your factory? Heaven Green Energy’s dedicated industrial team handles the complete commissioning ladder — from load audit through DISCOM coordination to live commissioning. Request a site assessment today or learn more about our industrial solar solutions.
Comparison: Industrial vs. Residential Solar Installation Process
| Process Stage | Residential (3–10 kW) | Industrial (100–500 kW) |
|---|---|---|
| Load analysis | Review 3–6 months bills | Full 12-month half-hourly demand audit |
| Site survey | Roof orientation, basic shadow | Structural engineering, detailed shadow modelling |
| System design | Standard templates | Custom SLD, cable calculations, PVSyst model |
| Equipment procurement | Standard retail | Manufacturer direct, with certification audit |
| Civil work | Basic mounting, minor waterproofing | Detailed structural, earthing, cable tray install |
| Electrical installation | 1–2 licensed electricians, 2–3 days | 10–20 person crew, 2–4 weeks |
| DISCOM approval | LT net metering, 2–4 weeks | Feasibility study, HT/LT protection review, 6–12 weeks |
| Commissioning | Basic energisation check | Full PR test, relay tests, handover documentation |
| O&M complexity | Annual cleaning, inverter monitoring | AMC contract, SCADA monitoring, quarterly inspection |
Advantages of a Structured Installation Process
- Accurate generation output matching design
- DISCOM approval without costly rework
- Warranty validity maintained from Day 1
- Safety compliance — no post-installation retrofits
- Clear O&M baseline for 25-year performance
- Full documentation for insurance and financing
Risks of Shortcutting the Process
- Over- or under-sized system vs. actual load
- DISCOM rejection requiring expensive redesign
- Roof leaks from improperly sealed penetrations
- Phase imbalance damaging factory equipment
- Anti-islanding failure — grid safety risk
- No documentation for insurance or asset value
O&M: Keeping Your Industrial Solar Plant at Peak Performance
Commissioning is the beginning, not the end, of the relationship between an industrial unit and its solar plant. A 500 kW system generating 7–8 lakh units per year represents approximately ₹60–80 lakh in annual electricity value. Small performance losses from neglected maintenance compound over 25 years into very large revenue losses.
Standard industrial solar O&M activities:
-
Monthly panel cleaning: Industrial environments accumulate dust, particulate matter, bird droppings, and chemical deposits faster than residential settings. For a 500 kW system in a dusty industrial area, uncleaned panels can show 5–10% generation loss within two months. Monthly cleaning (using demineralised water, soft brushes, and proper access equipment) is the minimum standard.
-
Quarterly inverter inspection: Check inverter fan operation, ventilation clearances, temperature logs from the monitoring system, and protection relay event logs. Identify and address any inverter alarms before they escalate to downtime.
-
Semi-annual electrical inspection: Thermal imaging of all DC combiner boxes, AC switchboards, and cable terminations to identify hotspots before they cause failures. Check earthing continuity. Test SPD functionality.
-
Annual performance ratio audit: Compare actual generation against the PVSyst model for the year, adjusted for actual irradiance (from pyranometer or weather station data). A PR below 75% triggers a detailed diagnostic to find underperforming strings, shaded areas, inverter losses, or soiling issues.
-
Inverter warranty management: Industrial inverter warranties typically require annual service by authorised service providers. Keep service records to protect warranty claims.
The complete guide to solar installation in Gujarat provides additional context on O&M best practices specific to Gujarat’s climate.
For industries evaluating the financial case for solar O&M investment, the why industrial leaders are choosing solar article covers the long-term asset management perspective.
How Heaven Green Energy Helps
Heaven Green Energy specialises in industrial-scale solar EPC across Gujarat, with dedicated project management, structural engineering, and DISCOM liaison capabilities built into every project.
- End-to-end EPC delivery: We own every rung of the commissioning ladder — load audit, engineering design, equipment procurement from ALMM-listed suppliers, structural civil work, electrical installation, DISCOM coordination, and commissioning handover. Explore our solar EPC capabilities.
- Industrial load audit and sizing: Our engineering team analyses your DISCOM data in detail, models demand charge savings, and sizes your system for maximum ROI — not maximum panel count. Discuss your project on our industrial solar page.
- DISCOM coordination expertise: We maintain active working relationships with all four Gujarat DISCOMs (MGVCL, UGVCL, DGVCL, PGVCL) and have a dedicated regulatory team to manage approvals without delay. Learn more about our Gujarat rooftop solar capabilities.
- Long-term O&M contracts: Post-commissioning AMC contracts including quarterly inspections, annual PR audits, and 24/7 remote monitoring — ensuring your industrial solar plant performs to design for its full 25-year life. Contact our team to discuss O&M for your facility.
Frequently Asked Questions
Q1. How long does it take to install a 200 kW solar plant on a factory in Gujarat?
For a straightforward 200 kW rooftop system on an LT-connected factory in Gujarat, the total project timeline from initial load audit to energisation is typically 10–14 weeks. The largest time variable is DISCOM approval — feasibility check, inspection scheduling, and meter installation can take 6–10 weeks with good coordination. Pre-engineering work (load audit, site survey, design) takes 2–3 weeks; civil and electrical installation takes 2–4 weeks.
Q2. Can we install solar on a metal sheet (GI sheet) industrial roof?
Yes. Metal sheet roofing is one of the most suitable roof types for solar because standing seam clamps allow zero-penetration mounting that preserves the roof’s weather integrity. The structural assessment must confirm the purlins and main beams can carry the additional dead load (typically 12–15 kg/m² for mounting structures and panels). Older or thin GI sheet roofing may require purlin reinforcement before mounting.
Q3. What is the minimum area required for a 100 kW industrial solar system?
A 100 kW solar system requires approximately 600–700 square metres of shadow-free roof area, assuming standard commercial panels (400–450 Wp, around 2 m² each). Industrial sheds of 2,000+ sq m are typically adequate for 200–400 kW. The usable area is always less than total roof area due to setbacks, parapet shadows, HVAC units, and access paths.
Q4. Do we need a separate energy meter for the solar plant?
Yes. Industrial solar plants require at minimum a generation meter (measuring total solar generation) and an import/export meter (bidirectional, installed by DISCOM for net metering). Some DISCOMs also require a dedicated solar energy meter as part of the net metering agreement. The meter specifications are provided by the DISCOM at the application stage.
Q5. Can a solar plant be installed while the factory is in operation?
Yes, with proper planning. Civil and structural work and panel mounting on the roof do not require factory downtime. The electrical switchover — connecting the solar AC output to the factory switchboard — requires a planned shutdown of the affected section, typically lasting 2–4 hours. DISCOM meter installation and commissioning also require brief grid disconnection. Pre-agreed shutdown windows during non-production hours (nights, weekends) minimise production impact.
Q6. What is the performance ratio (PR) and what should we expect for our industrial system?
Performance ratio is the ratio of actual system yield to the theoretical yield under the same irradiance conditions, expressed as a percentage. It captures all real-world losses — soiling, temperature derating, cable losses, inverter efficiency, shading. For a well-designed and well-maintained industrial system in Gujarat, PR of 78–83% is a realistic expectation. PR below 75% is a flag for investigation; PR above 80% consistently is excellent. Your EPC contractor should provide a PVSyst-simulated PR as part of the design, and actual PR should be monitored monthly.
Q7. What happens if our factory increases load significantly after solar installation?
If your factory’s electricity consumption increases significantly (e.g., adding a production line), the solar plant will offset a smaller percentage of the total consumption, but the absolute savings remain the same. You can consider adding additional capacity if roof space and DISCOM limits allow — the incremental cost of expansion is typically lower than the original per-watt cost because structural and electrical infrastructure is already in place. DISCOM capacity limits must be re-assessed for any expansion.
Q8. Is on-grid or off-grid solar better for a factory?
For factories with a reliable grid supply, on-grid solar is almost always the right choice. It eliminates the need for expensive battery storage, maximises solar utilisation through net metering, and provides continuous power during the many hours that solar is not generating. Off-grid systems are only appropriate for truly isolated sites with no grid access. Hybrid systems (with backup batteries) are justified for factories with frequent power cuts. Our on-grid vs off-grid vs hybrid guide provides a full comparison.
