Let’s look at an example where we compare both alternatives for a reasonably sized commercial project in the Netherlands. We cover some of the assumptions we have made in detail below.
Over the 15 year life of the Dutch SDE+ subsidy, the system owner can generate nearly 20% more profit with an East-West system at a slightly higher return on investment. While a south facing system in the Netherlands does produce nearly 7% more yield per Wp, this power is more costly given the current solar economics of 2018.
|Azimuth ||Annual yield per kWp (kWh/kWp) ||Annual yield per m² (kWh/m²) ||Annual savings (€) ||Cost of energy produced over 15yrs (€/kWh) ||ProjectIRR * |
|East-West ||934 ||127 ||20,443 ||0.059 ||19.30% |
|South ||997 ||100 ||16,000 ||0.076 ||17.20% |
*IRR excludes any fiscal/tax benefits
Autarco’s insured kWh Guarantee lowers the risk profile of the project for the bank, helping system owners and investors unlock more debt at lower costs. As a result, the additional initial investment required for an East-West system should not be a barrier to completion.
The drivers behind this result and some of the key factors to consider are discussed below. Regardless of the choice, Autarco’s kWh Guarantee, insured by Lloyd’s of London, delivers peace of mind to both installers and end customers by providing a minimum production level that protects your investment.
Yield per wattpeak
|Assumption ||Face Off result |
|Base Assumption: 10/12 degrees ||Win for South. 7.3% more yield/Wp. |
|Factor: Greater module pitches ||A 30 degree pitch south system will produce 13% more than a 10 degree pitch East-West system. |
As we all know, the yield per modules it at its best when the module is facing South. However, since the pitch of the solar panels in flat roof mounting systems is relatively low (10°-12°), the non optimal azimuth of East-West systems are more than compensated by other benefits.