Get what you pay for – pv magazine International

March 23, 2023 George Touloupas

From pv journal 03/23

Advances in PV module expertise have accelerated since 2018. The chart above – based mostly on CEA high quality assurance knowledge – reveals the commonest modules for utility-scale initiatives in 2017, which differ in expertise, has a mirror-backsheet construction and has 72 six-inch cells. – a sort of module launched in 2008.

Since 2018, we’ve got witnessed the transition from multicrystalline aluminum again floor area cells to mono PERC (passivated-emitter, rear contact) units; the adoption of half-cut cells; the dominance of bifacial, glass-glass merchandise; the introduction of multi busbar units; a transition to bigger desserts – 166 mm, then 182 mm, then 210 mm; the emergence of gallium doped p-type wafers; and, most not too long ago, the rise of n-type cells – largely n-TOPCon (n-type, tunnel-oxide, passivated contact) merchandise.

Wafer sizes have grown to cut back prices. The market share is at the moment divided between 210 mm and 182 mm wafers as a result of the benefits of every depend upon the mission specs. Because the manufacturing traces could be modified to supply any dimension, the market share is fluid.

Whereas “unique” codecs akin to 218 mm wafers are unlikely to develop, 182 mm variants are rising, akin to 182 mm large 185 mm merchandise designed to attenuate the white area between cells in excessive module route. Trina Photo voltaic not too long ago launched a 182 mm large by 210 mm excessive wafer. In the end, such variants depend on the M10 or G12 photo voltaic ingot platform and provide chains.

N-type actions

N-type (negatively-doped) options have made a formidable entry in 2022 with a number of gigawatts of TOPCon technology capability already being shipped. TOPCon and heterojunction (HJT) cells are the primary high-efficiency contenders to exchange mainstream, p-type PERC cells. The TOPCon and HJT cell structure can be utilized on p-type or n-type wafers however years of analysis have satisfied producers that solely n-type TOPCon and HJT variants can obtain the an optimum price effectivity relationship.

TOPCon is at the moment main the race as a result of legacy PERC cell manufacturing traces could be upgraded to supply them, whereas HJT requires retooling. TOPCon can also be cheaper, because of decrease capital and working prices.

The alternative high-efficiency expertise, interdigitated again contact (IBC) photo voltaic, is acknowledged because the “end-of-the-road” single-junction silicon PV expertise as a result of the larger than 26% conversion effectivity requires tandem cells. IBC cells have their contacts on the again facet, theoretically providing the best effectivity for single-junction units. Nevertheless, front-contact TOPCon and HJT cells could be transformed to back-contact units and plenty of producers appear to be planning such a improvement. Longi, nevertheless, selected a p-type IBC structure that doubtless makes use of PERC and TOPCon passivation.

The benefits and downsides of competing cell applied sciences are summarized within the following desk, the place IBC refers to any methodology of passivation, though properties akin to bifaciality and tooling capital expenditure (capex) are linked again – contact cells. An intense effort has been made to cut back the silver content material of HJT units.

Benefits and downsides of competing cell applied sciences

Levelized power prices

The tempo of n-type growth will speed up quickly as soon as expertise and price are overcome. Module consumers will settle for a value premium for n-type if excessive effectivity and improved power yield scale back capex and LCOE.

To measure such financial savings, CEA studied a 100 MW single-axis horizontal tracker system in Spain. PERC and TOPCon cells had been in contrast. Steadiness-of-system element prices are estimated from a number of sources, module price and value knowledge factors are taken from CEA’s “PV Worth Forecasting Report” and value monitoring. PVsyst is used to measure power yield.

For the evaluation, CEA outlined a “most value premium” metric to indicate the worth {that a} excessive effectivity module can generate in a PERC panel with out giving up the LCOE benefit.

CEA equates the LCOE for PERC and TOPCon programs, deriving the TOPCon module value by including the utmost premium to the PERC module baseline. Calculations present that TOPCon producers can cost a premium of as much as $0.0327/W in PERC with out struggling LCOE. Whereas consumers will not pay the best premium for the zero LCOE benefit, they are going to pay extra for some LCOE acquire. The next chart reveals the sensitivity of the LCOE benefit to the worth premium, with premiums under 50% of the utmost quantity leading to LCOE benefits of two.5% or larger. On this state of affairs, a premium of lower than $0.016/W could be cheap.

The worth premium for HJT modules – similar effectivity as TOPCon however with larger power yield – could be roughly 30% larger than TOPCon: about $0.005/W. HJT producers ought to work exhausting to cut back their price delta at TOPCon and goal for a great lead.

Modules decrease LCOE however pushing previous tipping factors accelerates the speed of change, making it tough to estimate improvement timelines. As an online of things affect LCOE, producer claims require verification.

In regards to the writer: George Touloupas is the senior director for expertise and high quality at photo voltaic and storage advisory Clear Power Associates.