---
title: "Bart Szablowski | ComparePV"
description: "Glossary terms and articles on ComparePV written by Bart Szablowski, with the data and sources behind each one."
source: "https://comparepv.com/authors/bart-szablowski"
---

# Bart Szablowski


## 01. Articles


#### Gross or net: why two shop prices are not comparable

[Open](https://comparepv.com/articles/gross-or-net-shop-prices)

Which solar panel shops print prices with VAT and which without, market by market, and how to turn any shop price into a figure you can compare.


#### How big are modern solar panels

[Open](https://comparepv.com/articles/how-big-are-modern-solar-panels)

Length, width, weight, watts per square metre and per kilogram for every module in our catalogue, and what the common formats mean for roofs and lifting.


#### How many solar panels does a household need

[Open](https://comparepv.com/articles/how-many-solar-panels-does-a-household-need)

Yearly kWh, your site's yield in kWh/kWp and one module's power give the module count. Worked for Warsaw, Munich and Seville, with the catalogue spread.


#### How to read a solar panel datasheet

[Open](https://comparepv.com/articles/how-to-read-a-solar-panel-datasheet)

A field by field guide to the solar module datasheet, with typical values from our catalogue and three arithmetic checks that catch a figure that is wrong.


#### Is a bifacial solar panel worth it?

[Open](https://comparepv.com/articles/is-a-bifacial-solar-panel-worth-it)

When the back of a bifacial module pays off, ground mount or roof, how bifaciality factors are spread in our catalogue and what bifacial modules cost per watt.


#### Pallet or single module: which is cheaper per watt?

[Open](https://comparepv.com/articles/pallet-or-single-module)

How much cheaper per watt is a pallet or multipack of solar panels than a single module? Live shop offers, same shop and same module, with counts.


#### How to choose panels for a hot climate

[Open](https://comparepv.com/articles/panels-for-a-hot-climate)

For a hot climate, compare the temperature coefficient before NOCT. A worked example, catalogue spreads and what a better coefficient costs in shops.


#### How to choose panels for a small roof or a balcony

[Open](https://comparepv.com/articles/panels-for-a-small-roof-or-balcony)

On a small roof or balcony, module size sets how many whole modules fit. A worked example with catalogue formats, efficiency bands and Polish shop prices.


#### Product warranty versus performance warranty

[Open](https://comparepv.com/articles/product-warranty-vs-performance-warranty)

The product warranty covers defects, the performance warranty a power schedule. How long each runs in our catalogue, by cell technology and maker.


#### The same module, different shop: how much prices differ

[Open](https://comparepv.com/articles/same-module-different-shop-price-spread)

How far apart shop prices sit for the exact same solar module, measured on live offers before VAT, and what stock status and shop habits add to the gap.


#### Solar panel price per watt by market

[Open](https://comparepv.com/articles/solar-panel-price-per-watt-by-market)

What a rooftop solar module costs per watt before tax in each market, from live shop offers, with the spread inside each country and what it means for a buyer.


#### STC power versus what you actually get

[Open](https://comparepv.com/articles/stc-power-versus-real-output)

Why a solar panel rarely delivers its rated power, and how much heat, weaker light and power tolerance take away, from catalogue figures and PVGIS.


#### TOPCon or PERC when buying today?

[Open](https://comparepv.com/articles/topcon-or-perc)

TOPCon or PERC? Efficiency, heat losses, warranted ageing and price per watt compared across our module catalogue and live Polish shop offers.


#### Voc, Isc and your inverter: reading voltage and current

[Open](https://comparepv.com/articles/voc-isc-and-your-inverter)

Where Voc and Isc sit on a datasheet, how far cold raises the voltage and heat the current, and which inverter limits they are checked against.


#### Warranty terms across manufacturers

[Open](https://comparepv.com/articles/warranty-terms-across-manufacturers)

Which manufacturers state the longest product and performance warranties in our catalogue, counted per company with a minimum number of datasheets each.


#### Which power class is cheapest per watt

[Open](https://comparepv.com/articles/which-power-class-is-cheapest-per-watt)

Does a watt cost less on a bigger solar module? Live shop offers split into five power classes, in Poland and across markets, with spreads and shop counts.


#### Cell technology and the temperature coefficient

[Open](https://comparepv.com/articles/cell-technology-temperature-coefficient)

Datasheet temperature coefficients grouped by cell technology across our catalogue, with medians, spreads and what the gap is worth on a hot roof.


---

Source: https://comparepv.com/authors/bart-szablowski