Let's say you have an uncommon solar panel now, with space for 3 tasks. You can post multiple jobs at once!
Open any buildings with multiple task space. For me its going to be the uncommon solar panel
You can see the counter in the upper right. Being that there is only capacity for 3 tasks, select up to 3. Once you have selected how many work orders you would like to post, click on the "POST WORK ORDER'" button.