diff --git a/.gitea/workflows/renovate.yaml b/.gitea/workflows/renovate.yaml
index cbbdcb6..3908505 100644
--- a/.gitea/workflows/renovate.yaml
+++ b/.gitea/workflows/renovate.yaml
@@ -2,9 +2,10 @@ name: Renovate
 
 on:
   schedule:
-    # UTC. Each repository's renovate.json decides when PRs open; daily runs pick up
-    # updates approved on its dependency dashboard.
-    - cron: "17 2 * * *"
+    # Every 4 hours from 09 to 21 UTC: 10-22 in Oslo in winter, 11-23 in summer. Each
+    # repository's renovate.json decides when PRs open; a run refreshes its dependency
+    # dashboard and opens the PRs approved there.
+    - cron: "17 9-21/4 * * *"
   workflow_dispatch:
 
 jobs:
diff --git a/README.md b/README.md
index b8dfa12..8830b04 100644
--- a/README.md
+++ b/README.md
@@ -1,7 +1,7 @@
 # renovate-runner
 
-Runs [Renovate](https://docs.renovatebot.com) on edb's repositories on git.neuf.no, daily from
-`.gitea/workflows/renovate.yaml`.
+Runs [Renovate](https://docs.renovatebot.com) on edb's repositories on git.neuf.no, every 4 hours between 10:00 and
+23:00, from `.gitea/workflows/renovate.yaml`.
 
 Renovate finds repositories by autodiscovery: every repository in `edb` it can write to. To add a repository, give
 Renovate write access to it. Renovate then opens an onboarding PR with a `renovate.json`, unless the repository already