Energy certificate - ventilation system / solar panels

Hello, I have a question about the energy certificate. I am somewhat at odds with my architect. At the start of construction, he promised me that to achieve the required energy values, I would not need a ventilation system or solar collectors. This could all be avoided through compensatory measures (thicker insulation, etc.). Now that it is about the energy certificate, I am suddenly hearing different things. I submitted my building application back in 2015. So I am not affected by the tightened Energy Saving Ordinance 2016. My question now is: What is the difference between the Energy Saving Ordinance 2009 and the Energy Saving Ordinance 2014 until 31.12.2015? According to the internet, the energy values are identical, and only heating boilers older than 30 years need to be replaced. Otherwise, the newly required energy savings (25%) only come into effect from 1.1.2016. Nevertheless, the energy savings in the Energy Saving Ordinance 2014 until 31.12.2015 can also be avoided by compensatory measures (15% through, for example, better insulation), and thus the ventilation system and solar collectors can be omitted. Is that correct? Thank you very much.